CVE-2025-2817Privilege escalation in Thunderbird Updater
- 8.8HighCVSS base score
- 0.67%Exploitation in 30 daysEPSS · top 48% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Thunderbird's update mechanism allowed a medium-integrity user process to interfere with the SYSTEM-level updater by manipulating the file-locking behavior. By injecting code into the user-privileged process, an attacker could bypass intended access controls, allowing SYSTEM-level file operations on paths controlled by a non-privileged user and enabling privilege escalation. This vulnerability was fixed in Firefox 138, Firefox ESR 128.10, Firefox ESR 115.23, Thunderbird 138, and Thunderbird 128.10.
Timeline
ID reserved
By mozilla
- 34 days later
· 34 days later
Published
- 12 months later
· 12 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| CISA-ADPADP (enrichment) | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | High8.8 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 0.67% · top 48% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.8.
Affected products
- unaffected 115.23 – ≤ 115.*
- unaffected 128.10 – ≤ 128.*
- unaffected 138 – ≤ *
- unaffected 128.10 – ≤ 128.*
- unaffected 138 – ≤ *
References
References7
- https://bugzilla.mozilla.org/show_bug.cgi?id=1917536 (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-28/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-29/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-30/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-31/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-32/ (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/05/msg00022.html (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2025-12689 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2025-2817)Record last updated .