Description
A compromised web process using malicious IPC messages could have caused the privileged browser process to reveal blocks of its memory to the compromised process. This vulnerability was fixed in Firefox 144, Firefox ESR 115.29, Firefox ESR 140.4, Thunderbird 144, and Thunderbird 140.4.
Affected products
mozilla: firefox; mozilla: thunderbird
References8
- www.mozilla.org/security/advisories/mfsa2025-81/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-82/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-83/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-84/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2025-85/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=1989899 Issue TrackingPermissions Required
- lists.debian.org/debian-lts-announce/2025/10/msg00015.html
- lists.debian.org/debian-lts-announce/2025/10/msg00031.html
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 37 · as of 9 November 2026
- CWE
- CWE-200
Could this be exploited in your environment?
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