Privilege Escalation in Mozilla Firefox (CVE-2026-16366)
Summary
Vulnerability in Mozilla Firefox (CVE-2026-16366). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 153.
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A weakness called CVE-2026-16366 was discovered in Mozilla Firefox.
In plain terms, it is improper privilege management.
Severity is High (CVSS 8.8/10). If exploited, attackers can leak data or disrupt key functionality.
What you should do: update the affected software to the latest version. If unsure, ask your IT team or search the vendor's site for "Mozilla Firefox CVE-2026-16366".
CVE-2026-16366 (Mozilla Firefox). Severity: High / CVSSv3 8.8. Category: CWE-269.
Response plan:
- Check the vendor advisory for affected versions and the patched release.
- If a vulnerable version is running in production, schedule maintenance (urgency from KEV/CVSS).
- If no patch yet, mitigate via WAF rule, disabling the affected feature, etc.
- Monitor logs / SIEM for known IOC and PoC signatures of this CVE.
PoCs and fix commits: see the 'References' section, MITRE, and NVD.
A weakness (CVE-2026-16366) in Mozilla Firefox. In plain words, it is improper privilege management.
Target versions of Mozilla Firefox (see vendor advisory). If running in production, identify exposure immediately.
Severity: High (CVSS 8.8/10). If exploited, attackers can leak data or disrupt key functionality.
Update to the patched release as listed in the vendor advisory. (Typical mitigation pattern for CWE-269)
If a patch is not yet available, consider disabling the affected feature, applying WAF rules, blocking via network ACLs, or isolating the vulnerable version.
Check version information, scan dependencies via SBOM, and monitor SIEM for IOC and PoC signatures related to this CVE.
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Ubuntu UBUNTU-CVE-2026-16366 mozjs52
References
- patch security@mozilla.org
- patch security@mozilla.org
- web nvd.nist.gov
- web security@mozilla.org
- web mozilla.org
- web github.com
- web mozilla.org