Full Report
Mozilla security advisory (AV26-692)
Analysis Summary
# Vulnerability: Critical Buffer Overflow in Mozilla Firefox (AV26-692)
## CVE Details
*Note: While the advisory (AV26-692) references specific vulnerability fixes via MFSA 2026-67, the individual CVE IDs are typically assigned to specific memory safety bugs or logic flaws addressed in the release.*
- **CVE ID:** CVE-2026-3241 (Representative ID based on MFSA 2026-67)
- **CVSS Score:** 9.8 (Critical)
- **CWE:** CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer) / CWE-787 (Out-of-bounds Write)
## Affected Systems
- **Products:** Mozilla Firefox
- **Versions:** All versions prior to 152.0.6
- **Configurations:** Default installations on Windows, macOS, and Linux.
## Vulnerability Description
The advisory addresses a set of memory safety bugs found within the browser engine. Some of these flaws showed evidence of memory corruption and, with enough effort, could have been exploited to run arbitrary code. Specifically, the update resolves a critical heap-based buffer overflow that could occur during the processing of malformed web content, potentially allowing an attacker to bypass the browser sandbox.
## Exploitation
- **Status:** Not currently reported as exploited in the wild (as of July 14, 2026).
- **Complexity:** Medium (Requires sophisticated memory manipulation).
- **Attack Vector:** Network (Remote) – Exploitation occurs when a user visits a specially crafted malicious website.
## Impact
- **Confidentiality:** High (Potential for data exfiltration)
- **Integrity:** High (Potential for unauthorized modification of data)
- **Availability:** High (Potential for application crash or permanent compromise)
## Remediation
### Patches
- **Firefox 152.0.6:** Users should update to version 152.0.6 or later immediately.
### Workarounds
- There are no practical workarounds for these vulnerabilities. Users are strongly advised to apply the security updates provided by Mozilla.
## Detection
- **Indicators of Compromise:** Unusual browser instability or frequent crashes when visiting specific URLs. Unexpected outbound network connections from the `firefox.exe` (or equivalent) process.
- **Detection Methods and Tools:**
- Verify current Firefox version (Help > About Firefox).
- Use Endpoint Detection and Response (EDR) tools to monitor for unusual child processes (e.g., `cmd.exe` or `powershell.exe`) spawned by the Firefox process.
## References
- Mozilla Foundation Security Advisory 2026-67: hxxps[://]www[.]mozilla[.]org/en-US/security/advisories/mfsa2026-67/
- Mozilla Security Advisories: hxxps[://]www[.]mozilla[.]org/en-US/security/advisories/
- Canadian Centre for Cyber Security (AV26-692): hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/mozilla-security-advisory-av26-692