In early 2022, a critical vulnerability—CVE-2022-26895—was identified impacting Microsoft Edge (Chromium-based). This exploit allows a local attacker to elevate their privileges, potentially taking control of affected devices. The significance of this vulnerability is heightened by its separation from similar CVEs like CVE-2022-24475, CVE-2022-26891, CVE-2022-26894, CVE-2022-26900, CVE-2022-26908, CVE-2022-26909, and CVE-2022-26912. Let's dive deeper to understand what makes CVE-2022-26895 unique, how it can be exploited, and what you should do to stay protected.

What is CVE-2022-26895?

CVE-2022-26895 is an Elevation of Privilege (EoP) vulnerability found in Microsoft Edge (Chromium-based). Specifically, it affects certain older versions of Edge before security updates were pushed by Microsoft.

Elevation of Privilege means that an attacker who already has limited access to a system (say, as a standard user) can exploit this vulnerability to gain higher, often administrative rights. Once this happens, the attacker can install programs, view, change, or delete data, and even create new accounts with full user rights.

How Does The Vulnerability Work?

While Microsoft has not published full technical details (to prevent widespread abuse), security researchers generally agree that this CVE stems from improper privilege validation in Edge's sandboxed environment. Edge, like Chrome, uses multiple processes to isolate tabs, plugins, and renderers for better security. But in this case, a bug allowed a local, low-privileged user to break out of the sandbox and execute code with higher-level privileges.

Proof-of-Concept (PoC) Overview

No fully public exploit code is available as of this writing, but several proof-of-concept scripts have been written and tested by security researchers as demonstrations. The PoC typically involves:

Running code within a sandboxed renderer process (such as JavaScript on a malicious web page).

- Triggering the bug within Edge’s IPC (Inter-Process Communication) or another process boundary to bypass checks.

Executing arbitrary code outside of the sandbox with enhanced privileges.

Here’s a conceptual example of what a local privilege escalation exploit might look like (note: this is a mockup for educational purposes):

// Conceptual C code demonstration for EoP in a browser
// This does NOT exploit the real CVE-2022-26895
#include <windows.h>
#include <stdio.h>

int main() {
    HANDLE hToken;
    TOKEN_PRIVILEGES tkp;

    // Attempt to open the current process token
    if (!OpenProcessToken(GetCurrentProcess(), 
                          TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY, &hToken)) {
        printf("Failed to open token\n");
        return 1;
    }

    // Lookup the LUID for the privilege
    LookupPrivilegeValue(NULL, SE_DEBUG_NAME, &tkp.Privileges[].Luid);

    tkp.PrivilegeCount = 1; 
    tkp.Privileges[].Attributes = SE_PRIVILEGE_ENABLED;

    // Attempt to enable the privilege
    AdjustTokenPrivileges(hToken, FALSE, &tkp, , (PTOKEN_PRIVILEGES)NULL, );
    if (GetLastError() != ERROR_SUCCESS) {
        printf("Failed to enable privilege\n");
        return 1;
    }

    printf("Privilege escalated (hypothetically)\n");

    // Now malicious code could run here with higher privileges
    return ;
}

In the real attack, the user’s code could ride along vulnerable Edge processes, or exploit flaws in inter-process communication to obtain a handle to higher privileged operations.

Real-World Impact

- Attackers must have local access: This isn't a remote code execution issue, but it is a big deal for environments where local users might be able to run arbitrary code (shared PCs, terminals, or weakly locked environments).
- Bypasses Edge’s strong sandboxing: Any flaw in browser process isolation is a high-value target for attackers, making this EoP issue a critical fix.
- Could be used as a pivot: Combining local EoP with a remote code execution bug can lead to full system compromise.

Patch and Mitigation

Microsoft fixed this issue promptly. The recommended action is simple: Update Microsoft Edge to at least version 100..1185.36 (or later). Edge updates itself by default, but verifying is always wise.

- Official Microsoft Security Guide: CVE-2022-26895 - Microsoft
- MSRC Security Update Details

Additional Resources

- NVD Entry for CVE-2022-26895
- Edge Stable Release Notes
- Chromium Security Whitepaper

It’s worth noting

> This CVE ID is unique from CVE-2022-24475, CVE-2022-26891, CVE-2022-26894, CVE-2022-26900, CVE-2022-26908, CVE-2022-26909, and CVE-2022-26912.

Each of these CVEs addresses different flaws—some possibly in other Chromium components or Windows integrations—so don’t mistake one fix for all. Always ensure your browser is up to date.

Conclusion

CVE-2022-26895 highlights how complex modern browsers like Microsoft Edge can have subtle, exploitable flaws that open doors for attackers. While there’s currently no public “point-n-click” exploit, details are enough for motivated attackers to attempt privilege escalation on outdated browsers.

The best defense: keep your software updated! And if you manage Windows environments, take a few minutes to verify that all systems are running the latest, patched versions of Microsoft Edge.

References

- Microsoft Security Response Center: CVE-2022-26895
- NVD National Vulnerability Database - CVE-2022-26895
- Chromium Sandbox Security


*For exclusive posts about the latest browser CVEs and practical security, follow our blog—a safe web starts with awareness!*

Timeline

Published on: 04/05/2022 20:15:00 UTC
Last modified on: 08/15/2022 11:19:00 UTC