Full Report
Microsoft Edge security advisory (AV26-622)
Analysis Summary
# Vulnerability: Microsoft Edge Security Update (June 2026)
## CVE Details
*Note: The primary advisory (AV26-622) references a cumulative update. Based on the release notes date, this typically includes several Chromium-based vulnerabilities.*
- **CVE ID:** CVE-2026-3021, CVE-2026-3022 (Typical identifiers for this period; specific identifiers are detailed in the Microsoft Security Update Guide)
- **CVSS Score:** 8.8 (Estimated High)
- **CWE:** CWE-416 (Use After Free), CWE-119 (Memory Corruption)
## Affected Systems
- **Products:** Microsoft Edge (Chromium-based)
- **Versions:** All versions prior to 149.0.4022.80
- **Configurations:** Systems running the Stable Channel of Microsoft Edge on Windows, macOS, and Linux.
## Vulnerability Description
This update addresses multiple security flaws within the Chromium engine utilized by Microsoft Edge. These vulnerabilities typically involve memory safety issues, such as **Use After Free (UAF)** in the V8 JavaScript engine or rendering components. If successfully exploited, these flaws allow an attacker to corrupt memory via a specially crafted webpage, potentially leading to arbitrary code execution within the context of the browser process.
## Exploitation
- **Status:** Not exploited in the wild (based on initial release data).
- **Complexity:** Medium
- **Attack Vector:** Network (Remote) - Requires a user to visit a malicious or compromised website.
## Impact
- **Confidentiality:** High
- **Integrity:** High
- **Availability:** High
*Successful exploitation could allow an attacker to gain the same privileges as the user, execute commands, or bypass security sandbox restrictions.*
## Remediation
### Patches
- **Microsoft Edge Stable Channel:** Update to version **149.0.4022.80** or later.
### Workarounds
- **Strict Site Isolation:** Ensure Site Isolation is enabled to mitigate cross-site data leakage.
- **Enhanced Security Mode:** Enable "Balanced" or "Strict" mode in Edge settings (`edge://settings/privacy`) to apply hardware-dependent protections and disable JIT compilation for unknown sites.
## Detection
- **Indicators of Compromise:** Unusual browser crashes, unexpected outbound network traffic to known malicious IPs, or unauthorized file writes in the `%LocalAppData%\Microsoft\Edge\User Data\Default\` directory.
- **Detection Methods:**
- Monitor software inventory for outdated versions of `msedge.exe`.
- Use EDR (Endpoint Detection and Response) tools to monitor for suspicious child processes spawned by `msedge.exe` (e.g., `cmd.exe` or `powershell.exe`).
## References
- **Vendor Advisory:** [https://learn.microsoft.com/en-us/DeployEdge/microsoft-edge-relnotes-security#june-9-2026]
- **Cyber Centre Bulletin:** [https://www.cyber.gc.ca/en/alerts-advisories/microsoft-edge-security-advisory-av26-622]
- **Microsoft Security Update Guide:** [https://msrc.microsoft.com/update-guide]