CVE-2025-10527: This vulnerability affects Firefox < 143, Firefox ESR < 140.3, Thunderbird < 143, and Thunderbird <
Source GCVE Database
Not known to be exploited · CVSS 7.1 High.
Data as of 29 Oct 2026, 22:52 UTC
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:LExploitation evidence
Disclosed: evidence found.
CVE published 16 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
Description
This vulnerability affects Firefox < 143, Firefox ESR < 140.3, Thunderbird < 143, and Thunderbird < 140.3.
References
- nvd.nist.gov/vuln/detail/CVE-2025-10527 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=1984825 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/09/msg00020.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2025/09/msg00026.html (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-73 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-75 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-77 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2025-78 (opens in a new tab)