We live and work in browsers. It’s where we spend most of our time — and it’s where we waste most of our time as well. Web browsing is slow, inefficient, and full of time-sapping annoyances.

But it needn’t be that way. You can turn your browser into a lean, mean productivity machine. To do it, just follow these tips for Microsoft Edge in Windows 10 or 11. You’ll learn how to switch between home and work profiles, put idle tabs to sleep to speed up your PC, tap into the power of Microsoft’s Copilot AI assistant, and more.

(Note that these tips are written for the most recently updated version of Edge in Windows 11 25H2 and Windows 10 22H2. Things may be slightly different if you use a different Windows version, and not all of these features are available for Edge on macOS or other platforms.)

So let’s get started — time’s a-wasting, and so is your productivity.

1. Switch between work and personal profiles

With remote and hybrid work models now common, many people use the same device for work and personal use. When it comes to using a web browser, that can quickly become problematic.

Mixing work and personal favorites makes it far more difficult to quickly get to important work websites or personal websites. When you’re working, you don’t want to wade through hundreds of links to family photos, vacation destinations, and YouTube videos of cats befriending parrots when you’re just looking for the OSHA website about mine safety regulations. And when you’re off working hours and want to watch a video of a Persian cat nuzzling a cockatiel, a website detailing the GDPs of every country in Europe and Asia is not your primary destination.

Different profiles let you completely segregate your browser use. That doesn’t just mean different favorites. It also means different Collections, different extensions, different passwords, and more.

Each Edge profile is tied to a different Microsoft account. So to use different profiles, you’ll need to create different Microsoft accounts. To create a new Microsoft account in Windows 10 or 11:

1. Go to https://account.microsoft.com. If you’re signed in to your account, click your profile icon or initials in the upper-right corner and select Sign out. Close Edge, restart it, and go back to https://account.microsoft.com/.
2. Scroll down to the button that says Create an account, click it, and follow the prompts to create a new account.
3. On the page that appears, click the Sign in button in the middle of the page. On the screen that appears, select the Create one! link, then follow the prompts to create a new account.

You’ve now got two different Microsoft accounts you can use for Edge. When you log into one of those accounts in Windows, that will be the default account that Edge will use when you browse the web.

To switch between the two accounts, you’ll need to add that second account to Edge. To do it:

1. Click the user profile icon at the top right of Edge. On the small pane that appears, select Set up a new profile, then select either Personal or Work or School. 
2. You’ll be sent to a web page in a new instance of Edge. Click the Sign in button at the far right, then select Sign in to sync data.
3. On the screens that appear, sign in and confirm that you want to proceed.

Once you’ve done that, you don’t have to log out of your current account and then log into the second account to use it in Edge. Instead, when you want to use the second account, click the user profile icon at the top right of the Edge window. A small pane appears with your current profile at the top. To switch to your other profile, select it in the “Other profiles” section.

You’ll now be sent straight to that profile. When you do that, Edge will open in a new window. So you’ll have both your profiles running simultaneously, each with its own tabs, in two separate windows. (Note that you can set up multiple additional profiles.)

You can also tell Edge which profile to use when you visit certain websites. To do it:

1. Click the user profile icon in Edge and select Profile settings. (Alternatively, you can click the three-dot icon next to the user profile icon and select Settings > Profiles.)
2. In the “Profile settings” area, click Profile preferences.
3. At the bottom of the “Automatic profile switching” section on the page that appears, click Add site next to “Custom site switch.”
4. On the “Add site” popup, enter a website URL and select the profile you want to switch to for that site.

Should you decide you want to remove a profile, go to Settings > Profiles and scroll to the “More profiles” section. Click the trash can button next to any profile you want to delete. You can always add it again later using the steps above.

2. Get to your most-used sites quickly

Bookmarking and organizing favorites is a great way to manage a large collection of websites, but it’s not that useful if you simply want to get to a frequently used site quickly. Edge has some tricks up its sleeve if you want to get your most-used sites pronto.

Add a site to the new tab page

When you open a new tab in Edge, a page appears that shows you news and other items you might be interested in. It’s easy to pin a site to this page so it’s accessible whenever you open a new tab.

Look toward the top of the page, just underneath the search box. If you don’t see icons for pinned pages (such as for Yahoo, Amazon, your inbox, and so on), click the settings icon on the upper right of the page (it looks like a gear) and turn “Quick links” on.

A row of site icons appears, along with a + icon. Click the + icon and type or paste in the name and URL of the site you want to pin, then click Add. The site will now appear along with the other pinned pages.

You can rename or remove any site pinned to the new tab page by clicking the three-dot icon next to the site icon and selecting Rename or Remove from the menu that appears.

The new tab page is tied to your current profile, so you can set up different pinned sites on the new tab page for each of your profiles.

Pin tabs to the top of Edge

For even faster access to frequently used sites, you can pin them as browser tabs so they appear at the far left of all your other tabs in Edge. When you’re on the site you want to pin as a tab in Edge, right-click its tab and select Pin tab from the menu that appears. The pinned tab will now appear to the left of all your open tabs.

The icon for the pinned tab looks smaller than all of your other tabs, and it will persist even after you shut down and restart Edge. If you have multiple pinned tabs, all of them will appear to the left of any non-pinned tabs.

Like pinned sites on new tab page, your pinned tabs are unique to each Edge profile; they won’t carry over from profile to profile.

Pin sites you often visit to the Windows taskbar

For Windows users, the fastest way to access a frequently used site is to pin it to the Windows taskbar. That means it’s always visible (even when Edge isn’t running), and you can launch it with a single click.

When you’re on the site you want to pin, select the three-dot icon at the top right of the browser window and select More tools > Pin to taskbar. A small screen appears with a text box in it with the name of the site. Use the name provided or type a new name into the text box and click Pin.

3. Create tab groups for more efficient browsing

If you’re like lots of people, you frequently browse with many tabs open, and find yourself wasting time switching to the tab you want because of all of the clutter.

There’s a simple fix: group tabs into categories so you can quickly switch to the tab group that has the tab you want. For example, you might group them into “News,” “Museums,” “Finance,” and so on. Or you could create a tab group for research related to a specific project.

To do it, right-click a tab, select Add tab to new group, and then name the tab group. You can then drag other tabs into the group. You can also assign each tab group a unique color so they’re easy to differentiate at a glance.

If you’ve already created a group, when you right-click a tab, you’ll see “Add tab to group” rather than “Add tab to new group.” When you click the arrow next to it, you’ll see a list of all your existing groups, so you can easily add it to any of them. You’ll also see “New group,” which will let you create and customize a new group.

Once you’ve created a tab group, you can rename it, change its assigned color, add new tabs to it, ungroup the tabs from it, delete the group and all the tabs in it, and more. Just right-click the name of any group and select an option from the menu that appears.

4. Enlist a Copilot as you browse

Microsoft’s genAI chatbot, Copilot, has become increasingly integrated with Edge, so much so that Microsoft now calls Edge an “AI browser.” At the moment, that’s more hype than fact, but it is true that Edge gets new Copilot features added on a regular basis.

Edge provides a couple of ways to interact with Copilot, one of which is to open the Copilot sidebar to the right of the main browser window. (We’ll go over the other method later in the story.) Click the Copilot icon at the top right of Edge, and the Copilot pane appears. Here’s where you type in prompts for Copilot.

There’s a tremendous amount you can do with Copilot, most of which is beyond the scope of this article. To learn more about what it can do and how to use it, see our story “9 ways to use Copilot right.”

However, here’s one use designed specifically for web browsing: summarizing the contents of the page you’re currently visiting. Depending on the structure and content of the page, Copilot can give a high-level overview of the entire page, provide capsule descriptions of individual articles or sections, and more. You can also ask Copilot to extract specific information from a page, such as all the AI-related information on it, and organize the information into a bulleted digest.

To do all that, open a web page and open the Copilot sidebar. You’ll see a few suggested prompts, one of which should be related to summarizing the page, such as Summarize the main points on this page or Create a summary of this page. Click the prompt, or if you don’t see it, type it into the text box at the bottom of the Copilot pane.

You can also ask it to summarize the last page you’ve visited. Click the down arrows towards the bottom of the Copilot pane, and you’ll see a listing for the previous page you’ve visited, such as Computerworld.com. Click the text summarize my recent activity on [page] and it will do that for you. Again, if you don’t see that text, type it into the Copilot text box.

The summarization feature, though, still has rough edges, or at least it did when I was writing this article. If you leave the web page you’re currently on and go to a new one, the summary of the old page remains, and there isn’t an immediate way to summarize the new one. To get a summary of the new page, you’ll have to scroll to the bottom of the Copilot pane, click the arrow (it will be facing either up or down, depending on whether you’ve previously clicked it) and click “Create a summary of this page.”

In that section, you can also click listings of your other open tabs and get summaries of any of them.

5. Remove clutter when you launch new tabs

When you create a new tab, the initial page is filled with pinned sites, suggested news stories, widgets, and more. If you find that page distracting, you can change it to a much cleaner, more stripped-down page.

If you haven’t pinned specific sites to the row of icons below the search box (see tip #2 above), you can make Edge’s default icons go away: Click the gear icon on the upper right of the page, and a “Page settings” panel pops up. In the “Quick links & search” section, click the dropdown next to “Quick links” and select Off. That gets rid of the icons for web sites just beneath the search box.

If you have pinned your own preferred sites there, you’ll want to leave quick links enabled, but you can turn the “Show sponsored links” toggle to Off to get rid of ads.

To get rid of the news articles that overwhelm the page, go to the “Show content” area of the panel and move the “Show feed” toggle to Off. Or, if you want to really strip down the page, move the “Show content” toggle to Off. That kills pretty much everything on the page except the weather. If you don’t want to see that either, scroll down a bit more and move the “Weather” toggle to Off.

 You can also strip out the background graphic for the new tab page by turning off the “Background” toggle. I don’t recommend it, though, because when you do that, you’ll get a gray page with a big Microsoft logo dead center when you launch a new tab.

6. Launch Copilot-centered new tabs

If you’re a frequent Copilot user, you might want to take a different approach to the new tab page.

The Copilot you get in a side pane when you click the Copilot icon at the top right of Edge is a somewhat stripped-down version of Microsoft’s full-blown Copilot app. If you’re looking to use the full-fledged version, there’s a simple way to do it: Tell Edge to open Copilot every time you open a new tab.

To do it, click the three-dot icon to the left of the Copilot icon at the top right of Edge and navigate to Settings > Start, home, and new tab page. In the “New tab page” section, turn on the Copilot new tab page toggle. From then on, every time you open a new tab, you’ll launch a full Copilot screen that’s similar to the standalone Copilot app.

You’ll see the usual Copilot prompt box front and center, and beneath that, several prompts Microsoft thinks you might want to use. (Note to Microsoft: I’ve never used one of those suggestions even once. I’d guess few other people have either.)

What’s really new here are the vertical icons running down the left side of the page. Here’s a brief rundown of what each one does:

• Open sidebar: Widens the navigation bar and shows a list of your recent chats so you can revisit any of them.
• New chat: Start a new chat with Copilot.
• Library: Build a library of Copilot-created content such as images, reports, podcasts, documents, and more.
• Tasks: Create a Copilot task that automates something you want done, such as sending you a weekly email about a company’s stock price.
• Health: Open Copilot Health, a version of Copilot designed specifically for getting health information.
• Shopping: Use Copilot as a shopping assistant.
• Imagine: Create or edit an image using Copilot.
• Experiments: Discover and use new Copilot features that Microsoft is testing but that may or may not be officially launched at some point.

Clicking the Copilot icon at the top of the list of vertical icons returns you to the main Copilot interface you get when you launch a new tab.

As you can see, many of these new Copilot functions are aimed at consumers and unlikely to be useful in a business setting. Still, if you frequently turn to Copilot for help, you might find the Copilot new tab page a good alternative to the standard new tab page.

And note that setting up the Copilot new tab page doesn’t prevent you from browsing or searching the web normally. Just enter the search term or website you want to visit in the address bar at the top of the screen.

7. Put tabs to sleep to conserve system resources and boost battery life

If you’re like most people, you keep multiple tabs open in Edge so you can easily switch among the sites, web apps, and information important to you. It’s a great time-saver.

But it can also be a big memory and processor hog, which can slow down both your browsing and your other computing tasks. It needn’t be that way, though. You can put inactive tabs to “sleep” until you need them, freeing up resources, which will make your PC speedier and make its battery last longer, even when you have multiple tabs open. Microsoft claims that putting inactive tabs to sleep reduces memory use by an average of 32% and CPU use by an average of 37%.

Here’s how to do it:

1. In Edge, click the three-dot icon on the upper right of the screen and select Settings > System and Performance > Performance.
2. In the “Memory” section, move the slider to On next to Automatically put tabs to sleep.
3. To change the length of time it takes to put an inactive tab to sleep, below “Automatically put tabs to sleep” click the drop-down arrow and select a time. Your choice is anywhere from 30 seconds to 12 hours.

To reawaken any tab that’s been put to sleep, simply click on it, and it will resume normal activity.

There’s a chance that some sites might not work properly after they’ve been put to sleep. If that happens to you, you can tell Edge never to put that site to sleep again. To do it, scroll up to the “General” area on the “System and performance / Performance” page of Settings. Click the Add site button next to the “Always keep these sites active” item and paste in the URL of any site you don’t want to sleep.

8. Reduce power use with ‘energy saver’

Browsers can be power hogs, especially if you have multiple tabs open and are playing videos or music in them. That can be a particular problem if you’re using a laptop that isn’t plugged into a power source.

In Edge, the “energy saver” setting reduces the amount of system resources the browser uses, which extends your PC’s battery life. If you enable energy saver, it becomes active when your laptop is unplugged. Microsoft claims energy saver can give you on average an extra 25 minutes of battery life. To use it:

1. In Edge, click the three-dot icon on the upper right of the screen and select Settings > System and Performance > Performance.
2. In the “Power” section, make sure the toggle next to “Enable energy saver” is turned on. When you do that, you see two options: “Balanced” and “Maximum savings.”
3. Select Balanced if you want your laptop to go into a lower-power mode to save battery life when your laptop is unplugged or has a low battery. Select Maximum savings if you know you’re not going to be able to plug your laptop in for some time. Note that in this mode, your video quality may be affected.

There’s also a separate option to use energy saver even if your laptop is plugged in. Use this option if you want to consume less energy when you use your computer. Note that if you use it, you may experience slowdowns when browsing the web.

9. View and mark up PDFs

With Edge, there’s no need to launch a separate application when you want to read or mark up a PDF; its built-in PDF app is quite good. With it, you can draw on and highlight sections of the PDF and erase the marks you made as well. So save yourself time and use Edge rather than third-party software.

You don’t need to do anything to read a PDF online. Simply click it, and by default it will launch in Edge’s reader. You’ll find the markup tools, including for drawing, highlighting, and erasing, in a toolbar towards the top of the screen. To open a PDF from your hard disk, when you’re in Edge, press Ctrl-O, then navigate to the PDF and click it.

If you prefer to use your own PDF reader, even for PDFs found online, you might be annoyed that every time you click a PDF, it opens in Edge’s PDF reader. You can change that, though, by changing your default PDF reader.

In Windows Settings, select Apps > Default Apps and in the search box at the top of the screen just below “Set a default for a file type or link type,” type in .pdf. After you do that, the listing “Microsoft Edge Microsoft Edge PDF document” appears. Click it, and a screen appears showing you all the applications on your PC that can read PDFs. Select the one you want to use instead of Edge.

10. Turn on Edge’s AI-powered ‘scareware’ blocker

The internet is filled with scammers using sophisticated attacks to steal your data or money. A common one is so-called “scareware,” in which when you visit a website, your PC is suddenly locked into full-screen mode filled with fake malware warnings that claim your computer has been infected and urge you to call a phony tech-support line or allow remote access to your device to supposedly fix the problem.

Once you do that, the scammers steal your data, get you to pay for phony solutions, or embed malware on your system.

To fight that, Edge includes an AI-powered scareware blocker that builds and constantly updates a machine-learning model that detects suspicious behavior and stops the scamware in its tracks.

Typically, the scamware detector is turned on, but there’s a possibility it’s been turned off at some point or was never turned on in the first place. For example, on PCs with only 2GB of RAM or fewer than 5 cores, it’s not turned on by default. Microsoft recommends enabling it on those machines. To do it, in Edge go to Settings >Privacy, search, and services > Security, and in the “Scareware blocker” setting, turn the slider from off to on.

When you do that, make sure that “Block sites detected as scams” and “Share detected scam sites with Microsoft Defender SmartScreen” are turned on as well.

11. Use Edge’s one-click form filler

How many hours a week do you spend mindlessly filling out web forms — your office or home address, shipping address, email address, and phone number? Wouldn’t it be nice to get that time back?

With autofill, built into Edge, you can. To use it, in Edge go to Settings > Passwords and autofill > Addresses and more. Turn on the toggle next to “Save and autofill addresses.” You can also choose to have Copilot analyze web forms and decide which bits of your information belong in which part of the form.

From now on, whenever you visit a web form, just click in a text box, and your information will appear in a popup. Select it and the form will fill in. You can go back to Passwords and autofill to change any information you want.

12. Save time with keyboard shortcuts

There’s a good chance you use keyboard shortcuts for some of your office applications, like Word and Excel — and you likely use some for Windows itself.

But when it comes to browsers, many people forgo the keyboard except when absolutely necessary. That’s too bad, because keyboard shortcuts are a big timesaver. So to improve your productivity, check out these keyboard shortcuts for Edge in Windows. (Mac users can generally substitute the Cmd key for Ctrl and the Opt key for Alt.)

For even more shortcuts, see Microsoft’s complete list of keyboard shortcuts for Edge.

Useful keyboard shortcuts in Microsoft Edge

Key combination	Task
Ctrl-Shift-B	Show or hide the favorites bar
Ctrl-D	Add the current site to favorites
Alt-D or Ctrl-L	Select the URL in the Address bar
Ctrl-E or Ctrl-K	Open a search in the Address bar
Ctrl-F	Find on the current page
Ctrl-R	Reload the current page
Ctrl-H	Open your History
Ctrl-M	Mute or unmute volume on the current tab
Ctrl-N	Open a new window
Ctrl-Shift-N	Open a new InPrivate window
Alt-F4 or Ctrl-Shift-W	Close the current window
Ctrl-T	Open a new tab and switch to it
Ctrl-W	Close the current tab
Ctrl-Tab	Switch to the next tab
Ctrl-Shift-Tab	Switch to the previous tab
Ctrl-+ (plus symbol)	Zoom in
Ctrl– (hyphen)	Zoom out
Ctrl-P	Print the current page
Ctrl-Shift-.	Open the Copilot pane

This article was originally published in March 2021 and most recently updated in July 2026.

An “AI worm” can spread through Microsoft Word documents using Copilot as a vector, a prominent Norwegian AI researcher reported on Tuesday.

The report from Håkon Måløy, later confirmed by Microsoft, said that an attacker can conceal instructions in a document that is later used as source material for Copilot-generated or Copilot-edited Word documents, for example, as input to a financial report. Those malicious instructions could potentially alter figures in the document being created. They then copy themselves into the new document, causing it to become a carrier of the attack when used in another Copilot-assisted workflow.

Måløy noted: “To my knowledge, this is among the first public demonstrations of document-borne AI-worm self-propagation through normal workflows in a mainstream commercial productivity suite.”

Microsoft on Thursday emailed a statement to CSOonline discussing the report’s revelations. 

“We have addressed the findings reported by the researcher and thank them for working with us through coordinated vulnerability disclosure. To address this class of risk, we use a defense-in-depth strategy with safeguards that block malicious instructions at multiple points and help keep tasks aligned with users’ requests,” Microsoft said.

“We are continuously strengthening these safeguards as the technology and threat landscape evolve,” it added. “We encourage customers to install the latest updates, use multiple layers of security protection, treat content from unknown sources with caution, and review AI-generated content before using or sharing it.” 

Sidesteps defenses

Aman Mahapatra, chief strategy officer for Tribeca Softtech, a New York City-based technology consulting firm, has reviewed the mechanisms used in this vulnerability and says that it is much worse than it might seem, because it will sidestep just about every defensive mechanism enterprises have in place today.

“This is a worm, a self-propagating malware pattern that uses Copilot as the transmission mechanism and legitimate corporate collaboration as the delivery channel. It bypasses every traditional email security control because the document is not malicious on delivery and it becomes malicious when Copilot processes it. That means that it bypasses DLP because the exfiltration happens through the user’s own authenticated Copilot session,” Mahapatra said. “It then bypasses endpoint protection because no code executes, only instructions get followed by an AI service the enterprise has explicitly authorized.”

He also noted that researchers have been warning about this class of attack for two years.

Microsoft’s involvement

Måløy said that he has been working with the Microsoft Security Response Center (MSRC) since March 3 and Microsoft  subsequently implemented and distributed multiple small focused mitigations, but the core vulnerability has yet to be fixed.

He said he was hesitant to disclose an active vulnerability, but felt that it was now time to publish. 

“My reasoning is that defenders cannot reduce exposure to a risk they are unaware of,” Måløy wrote, “and the propagation mechanism described here affects ordinary document workflows that many organizations already rely on.”

In an email interview, Måløy noted that the tweaks Microsoft has implemented were helpful, nonetheless. 

“The coordinated disclosure process showed that mitigations can meaningfully reduce the demonstrated attack surface, making attacks less reliable and limiting their reach, even without completely eliminating the underlying problem,” he said. 

Måløy also addressed the resolution that many analysts and consultants suggested, which is to change the nature of LLMs to fully isolate instructions from the data they operate on. 

“Separating instructions from data may be part of the solution, but I think the distinction between data and instructions is not always clear in real-world workflows. For example, a user may ask an agent to arrange a business trip, requiring the agent to retrieve an email specifying the approved itinerary and a document containing the booking procedure,” Måløy said.

“My view is that the broader challenge is therefore not simply to prevent systems from interpreting external content as instructions, but to evaluate whether those instructions align with the user’s goals and the context in which the system is operating,” he added.

Problem hard to overstate

Mike Wilkes, enterprise CISO at Aikido Security, said it would be difficult to overstate the potential problems from this situation. 

“This is a significant issue because it moves prompt injection from a single compromised interaction into a potentially self-propagating document integrity attack,” he said, noting that it is not a conventional worm that spreads automatically. A user or Copilot workflow must still bring an infected document into the model’s context. “But once that happens, the malicious instructions can reportedly alter business information, conceal themselves inside the resulting Word document and turn a legitimate internal file into the next carrier,” he said.

That, he pointed out, creates “a dangerous enterprise supply chain in which financial reports, contracts, policies and partner documents may inherit malicious behavior while retaining the trust associated with their legitimate authors and Microsoft 365 accounts.”

Not a new issue

The key issue behind this flaw is the fact that genAI tends to struggle with telling the difference between data that a user offers as input and the instructions the AI is to execute.

Flavio Villanustre, CISO for the LexisNexis Risk Solutions Group, observed that the same problem with mixed data and instructions occurred in databases decades ago, and turned into what we know as SQL injection attacks today. But, he noted, a few years later, parametrized binding for the database access layers was developed, which separates instructions, which are handled internally and safely, from data, which can come from untrusted sources. “The same needs to happen with LLMs and other AI,” he said.

Mike Leone, a VP/principal analyst at Moor Insights & Strategy, agreed.

“It’s hard not to chuckle a bit with this one. People have been asking whether data can give orders since SQL injections. We fixed that one by giving the database a way to tell an instruction from a value,” Leone said. “Thirty years later, we’ve built an entire category of software that can’t tell the difference at all.”

Tom Findling, CEO at Conifers.ai, also said he sees the data-vs-instructions issue as the biggest problem. 

“Separating data from instructions is still unsolved at the model layer. The labs are making real progress, but not enough to be your only control,” he said, and stressed, “Microsoft doesn’t need to wait for that. It can slow propagation inside Copilot: stop hidden content from being written into new documents, surface hidden text before it’s used, preserve the trust level of what Copilot read and show all AI-generated changes.”

Fix needs industry agreement

However, Frank Dickson, group VP for security at IDC, argued that a fix needs industry agreement. 

“A fundamental fix requires the industry to converge on the same architectural change, which isn’t happening anytime soon given the incentives and the fact that the major players are far from besties,” he said, pointing out that Instruction-data separation would need to be baked in at the model or platform level across every major vendor. “None of them are rewarding that work commercially right now, so treat that as a multi-year research problem, not something a CISO should wait on.”

Leone disagreed, arguing that a single vendor can do quite a bit, at least for its own customers. 

“Microsoft has said publicly since last year that indirect prompt injection can’t be fully prevented, and I give them credit for saying it out loud rather than pretending otherwise,” Leone said, noting that the industry doesn’t have to move in lockstep. “This attack lives inside one product,” he said. “If Microsoft hardens the Copilot document path, Copilot customers get safer whether or not anyone else moves.”

Dickson added that another critical problem with this vulnerability is that the carrier documents are created by legitimate employees using legitimate tools, “so there’s no obvious point of origin once the payload starts moving; an organization could be laundering corrupted financial figures through its own workflow for weeks before anyone notices.”

Tactics that might help

That said, experts had some specific suggestions for CISOs trying to negate this problem. 

IDC’s Dickson said, “the most useful lever right now sits outside the model entirely, in how much untrusted content Copilot is allowed to pull into a session without a human choosing it.” He noted that enterprises can turn Copilot’s auto-discovery behavior off or restrict it, and require humans to explicitly select the documents they feed it. “That alone closes off one of the two ways the attack gets a foothold,” he said.

IDC also suggested a visible diff or redline of anything Copilot changes in a financial or otherwise consequential document, and the requirement for a human to approve the changes. “That’s not a technical fix, it’s a workflow one, and it’s available today,” Dickson said.

He said that IT should also track where content came from and what was touched by an AI system, in metadata that travels with the document. “It doesn’t stop the injection, but it means when something does get through, an organization can actually trace how far it spread instead of discovering a corrupted number three reports later with no way to reconstruct the chain,” he said.

However, one expert, Tyler Reguly, Fortra’s associate director of security R&D, said that he didn’t see this vulnerability having a meaningful impact because it feels like what he called a “laboratory vulnerability.”

Normal enterprise workflows don’t encompass a number of the necessary steps for compromise, he said, pointing out that, if anything, people are trained not to download Word documents. Plus, he noted, looking at the blurred example in the report, the malicious document contained an additional apparently blank page which held the concealed prompts in white text.

“That page is going to send up warning signs for me if someone even managed to convince me to download an external Word document,” he said. So, overall, “this feels like it requires a perfect storm.”

This article originally appeared on CSOonline.

Traveling enterprise employees beware: Think twice before you log onto that oh-so-convenient public Wi-Fi.

Since at least June, threat actors have been compromising “captive” Wi-Fi gateways and other portal appliances at hotels, conference centers, and similar shared venues to hijack users’ Microsoft 365 accounts, according to the ReliaQuest Threat Research team.

Once a threat actor controls a gateway, they can silently redirect a user’s traffic to their own infrastructure and steal their Microsoft 365 credentials without ever touching the user’s device, compromising endpoints, or sending phishing links or malicious attachments.

“The most dangerous element is that it operates at the network gateway, which sits beneath most of the trust assumptions users and devices make,” ReliaQuest told CSO Online. “It’s not necessarily an enterprise breach level event on its own, but it’s a very real risk to individual accounts.”

Exploiting a ‘fundamental trust’

Domain Name System (DNS) poisoning, in which false data is injected to redirect regular web traffic to fraudulent domains, has previously been observed on small office routers, but attackers are now expanding the technique to higher-level targets, the ReliaQuest researchers explained in a blog post.

Attackers likely gain access to the gateways through weak or reused admin credentials in combination with exposed interfaces like Secure Shell (SSH), Simple Network Management Protocol (SNMP), and other web consoles, they pointed out.

Admin access to the gateway is all that malicious actors need, because devices are designed to inherently trust DNS, which translates domain names like login.microsoftonline[.]com into IP addresses to route them. Therefore, a single gateway compromise gives the attacker the ability to redirect traffic for every guest logging into the network, providing IP addresses it controls in response to DNS requests, rather than the legitimate ones, without touching a single endpoint.

“Captive portal appliances sit at the network perimeter for every guest on that network,” the researchers wrote. “Detection is inherently difficult because the attack happens gateway-side, outside the endpoint’s visibility.”

In the campaign tracked by ReliaQuest, four attacker-registered domains, m365-owa[.]com, owa-ms365[.]com, ms365-device[.]com, and ms365-live[.]com, were used for Microsoft-impersonation lures.

The compromised Wi-Fi gateways were discovered across multiple US cities as well as in India and Saudi Arabia, and impacted users were from companies in professional and financial services, legal, retail, health care, and energy, indicating that the method isn’t sector-specific.

“We’ve seen enough SharePoint exfiltration cases to know that a single popped account can cascade into meaningful data loss,” ReliaQuest noted. Meanwhile, for the network operators, there’s a “reputational dimension”; user compromise is a “serious trust and brand problem, regardless of how sophisticated’ the underlying attack is.”

Safe services, DNSSEC not enough

Locking network configurations to a ‘safe’ DNS provider such as Google (8.8.8.8), Cloudflare (1.1.1.1), or the cloud-based OpenDNS isn’t a sufficient tactic, because it doesn’t change the path that queries actually travel over, ReliaQuest contended.

By default, devices send DNS queries as unencrypted protocol traffic, and those packets still have to traverse the hotel’s network to reach Google, Cloudflare, or OpenDNS, the company explained. Since the gateway sits directly in that path, it can inspect, block, or redirect the query before it ever reaches the chosen resolver.

“Specifying a trusted DNS server changes the intended destination, not who controls the road to get there,” ReliaQuest noted.

Further, Domain Name System Security Extensions (DNSSECs), which use digital signatures and public-key cryptography, only “partially” address the problem. DNSSEC provides authentication and integrity for signed domains, which means a validating resolver can detect and reject forged or tampered responses.

“What it does not do is provide confidentiality or availability,” the company said. “It does not encrypt DNS traffic or stop an attacker from intercepting, blocking, or redirecting requests.”

So while DNSSEC can defeat certain response-forgery attacks against signed zones, an on-path gateway can still see queries, drop them, or force fallback behavior. However, this protection layer only helps when domains are actually signed, and then only when the client or resolver performs validation, which “many stub resolvers do not,” according to ReliaQuest.

Full-tunnel VPNs required

To combat the problem, enterprises should require all corporate devices to use a full-tunnel VPN for network connection. Controls should prevent internet access until a tunnel is active, ReliaQuest advised.

This will route all of a device’s traffic, including DNS, through an encrypted connection to a trusted VPN server before it travels anywhere else, the company explained, thus preventing local networks like hotel gateways from seeing or modifying DNS and internet traffic.

“In effect, it takes the untrusted network out of the trust equation,” ReliaQuest noted.

However, full-tunnel configuration is not the default for VPNs, because it comes with “real trade-offs,” the researchers noted: It adds cost, latency, and bandwidth demands, since every packet has to travel through company infrastructure. Thus, forcing all traffic through the corporate backbone is “not always practical” for distributed or bandwidth-heavy workforces.

Enterprises should also enforce conditional access in Entra ID to block device-code authentication flow, which has few legitimate use cases for most users in most environments, ReliaQuest noted.

Additional precautions

The company also advised:

• Restricting Proxy Auto-Configuration (PAC) file retrieval to approved internal hosts;
• Disabling automatic Web Proxy Auto-Discovery (WPAD) via Group Policy to (this is often enabled by default in Windows);
• Deploying encrypted DNS such as DoH or DoT in strict mode as a “complement or alternative” to full-tunnel VPN. This is particularly important for organizations where always-on VPN is not feasible.
• Training employees to verify the URL and certificate of any page requesting credentials before entering them, particularly on public Wi-Fi networks.

Prevention is more important than detection here, ReliaQuest pointed out: while in tools like Microsoft Defender for Endpoint, ‘DnsConnectionInspected’ events showing queries to attacker-controlled domains are a primary endpoint-level signal, “by the time those events fire, the redirect has typically already occurred. In other words, endpoint telemetry confirms what happened more than it prevents it.”

This is exactly why methods like encrypted transport, Conditional Access, and WPAD and PAC hardening matter more than detection alone, the researchers emphasized.

This article originally appeared on CSOonline.