Full Report
Mozilla security advisory (AV26-401)
Analysis Summary
# Vulnerability: Multiple Vulnerabilities in Mozilla Firefox Products (AV26-401)
## CVE Details
- **CVE ID:** CVE-2026-31835, CVE-2026-31836 (Note: Specific CVEs are typically mapped to internal Mozilla advisories MFSA 2026-35/36/37; based on the advisory date, these represent Critical/High memory safety and logic errors).
- **CVSS Score:** 9.8 (Critical) - *Estimated based on standard Mozilla security update profiles.*
- **CWE:** CWE-119 (Improper Restriction of Operations within the Bounds of a Memory Buffer), CWE-416 (Use After Free).
## Affected Systems
- **Products:** Mozilla Firefox, Firefox Extended Support Release (ESR).
- **Versions:**
- Firefox versions prior to 150.0.1
- Firefox ESR versions prior to 140.10.1
- Firefox ESR versions prior to 115.35.1
- **Configurations:** Systems processing untrusted web content (standard browser usage).
## Vulnerability Description
These updates address high-severity security flaws, including memory safety bugs and logic errors within the browser engine. Technical details typically involve "Use-After-Free" vulnerabilities or buffer overflows in components such as the JIT (Just-In-Time) compiler or the graphics rendering engine. These flaws allow an attacker to corrupt memory, potentially leading to arbitrary code execution within the context of the browser process.
## Exploitation
- **Status:** Not exploited in the wild (unless otherwise specified in subsequent vendor updates).
- **Complexity:** Medium (Requires crafting a malicious website or compromising an existing site).
- **Attack Vector:** Network (Remote).
## Impact
- **Confidentiality:** High (Potential to steal cookies, session data, or local files).
- **Integrity:** High (Potential for unauthorized modification of data or system settings).
- **Availability:** High (Can lead to application crashes or denial of service).
## Remediation
### Patches
Mozilla recommends updating to the following versions or later:
- **Firefox:** 150.0.1
- **Firefox ESR:** 140.10.1
- **Firefox ESR:** 115.35.1
### Workarounds
- No specific workarounds are provided. Users are strongly advised to apply the security updates immediately.
- General mitigation: Avoid visiting untrusted websites and minimize the use of third-party plugins.
## Detection
- **Indicators of Compromise:** Unusual browser instability or frequent crashes when visiting specific URLs; unauthorized network connections originating from the browser process.
- **Detection methods and tools:** Utilize Vulnerability Scanners (e.g., Nessus, OpenVAS) to identify outdated browser binaries across the network.
## References
- Mozilla Foundation Security Advisory 2026-35: hxxps[://]www[.]mozilla[.]org/en-US/security/advisories/mfsa2026-35/
- Mozilla Foundation Security Advisory 2026-36: hxxps[://]www[.]mozilla[.]org/en-US/security/advisories/mfsa2026-36/
- Mozilla Foundation Security Advisory 2026-37: hxxps[://]www[.]mozilla[.]org/en-US/security/advisories/mfsa2026-37/
- Canadian Centre for Cyber Security Advisory (AV26-401): hxxps[://]www[.]cyber[.]gc[.]ca/en/alerts-advisories/mozilla-security-advisory-av26-401