Full Report
Microsoft Edge security advisory (AV26-591)
Analysis Summary
# Vulnerability: Microsoft Edge Multiple Vulnerabilities (June 2026)
## CVE Details
- **CVE ID:** CVE-2026-11645 (Primary focus)
- **CVSS Score:** Not explicitly listed in advisory, but categorized as high-priority due to exploitation status.
- **CWE:** Not specified in the primary advisory.
## Affected Systems
- **Products:** Microsoft Edge (Chromium-based)
- **Versions:** All versions prior to 149.0.4022.62
- **Configurations:** Systems running the Stable Channel of Microsoft Edge.
## Vulnerability Description
While the advisory does not provide a deep technical deep-dive, it addresses vulnerabilities within the Chromium engine and Edge-specific components. CVE-2026-11645 likely refers to a memory corruption or logic flaw within the browser's rendering engine or javascript engine (V8), which is common for "exploited in the wild" Edge/Chrome vulnerabilities.
## Exploitation
- **Status:** **Exploited in the wild.** Microsoft has indicated that an exploit for CVE-2026-11645 exists and is being utilized.
- **Complexity:** Low to Medium (based on active exploitation status).
- **Attack Vector:** Network (Remote). Typically triggered by a user visiting a malicious or compromised website.
## Impact
- **Confidentiality:** High (Potential for data theft and session hijacking).
- **Integrity:** High (Potential for unauthorized modification of browser data).
- **Availability:** High (Potential for browser instability or system compromise).
## Remediation
### Patches
- **Microsoft Edge Stable Channel:** Update to version **149.0.4022.62** or later.
### Workarounds
- No specific workarounds are provided. Rapid patching is the only recommended course of action for browsers with active exploits.
## Detection
- **Indicators of Compromise:** Monitor for unusual outbound network traffic from `msedge.exe` to unknown IPs or unauthorized file system writes within the user's AppData directory.
- **Detection methods and tools:**
- Use Vulnerability Management scanners to identify outdated browser binaries.
- Check the version via the "About Microsoft Edge" settings page.
## References
- **Vendor Advisory:** hxxps[://]learn[.]microsoft[.]com/en-us/DeployEdge/microsoft-edge-relnotes-security#june-9-2026
- **Canadian Centre for Cyber Security:** hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/microsoft-edge-security-advisory-av26-591