CVE-2025-9185

Memory safety bugs present in Firefox ESR 115.26, Firefox ESR 128.13, Thunderbird ESR 128.13, Firefox ESR 140.1, Thunderbird ESR 140.1, Firefox 141 and Thunderbird 141. 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 142, Firefox ESR 115.27, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.

Score

CVSS 3.1 8.1 High

Status

Modified - security@mozilla.org

Published

2025-08-19

Last modified

2026-10-05

Weaknesses

CWE-119

Affected products

• Firefox (Mozilla)
• Thunderbird (Mozilla)

References

• https://bugzilla.mozilla.org/buglist.cgi?bug_id=1970154%2C1976782%2C1977166
• https://www.mozilla.org/security/advisories/mfsa2025-64/
• https://www.mozilla.org/security/advisories/mfsa2025-65/
• https://www.mozilla.org/security/advisories/mfsa2025-66/
• https://www.mozilla.org/security/advisories/mfsa2025-67/
• https://www.mozilla.org/security/advisories/mfsa2025-70/
• https://www.mozilla.org/security/advisories/mfsa2025-71/
• https://www.mozilla.org/security/advisories/mfsa2025-72/
• https://lists.debian.org/debian-lts-announce/2025/08/msg00018.html
• https://lists.debian.org/debian-lts-announce/2025/08/msg00016.html