CVE-2026-16361: Buffer Overflow (CVSS 9.8)

Description

Memory safety bugs present in Firefox ESR 115.37 and Firefox ESR 140.12. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 115.38 and Firefox ESR 140.13.

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CVSS v3.1 Score

9.8

CRITICAL

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-119 Buffer Overflow

References

Other References

https://bugzilla.mozilla.org/buglist.cgi?bug_id=2029734%2C2036518 https://www.mozilla.org/security/advisories/mfsa2026-69/ https://www.mozilla.org/security/advisories/mfsa2026-70/

Frequently Asked Questions

What is CVE-2026-16361? +

Memory safety bugs present in Firefox ESR 115.37 and Firefox ESR 140.12. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox ESR 115.38 and Firefox ESR 140.13. It has a CVSS v3.1 base score of 9.8 (CRITICAL).

How severe is CVE-2026-16361? +

CVE-2026-16361 has a CVSS v3.1 score of 9.8 out of 10, rated CRITICAL. This is a critical vulnerability that should be patched immediately.

How do I check if I'm vulnerable to CVE-2026-16361? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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