CVE-2025-1009Use-after-free in XSLT
- 9.8CriticalCVSS base score
- 1.2%Exploitation in 30 daysEPSS · top 31% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
Description
An attacker could have caused a use-after-free via crafted XSLT data, leading to a potentially exploitable crash. This vulnerability was fixed in Firefox 135, Firefox ESR 115.20, Firefox ESR 128.7, Thunderbird 128.7, and Thunderbird 135.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. CISA's SSVC rates its exploitation: a proof of concept is public.
Timeline
ID reserved
By mozilla
Published
- 14 months later
· 14 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 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVDNVD · Modified | 3.1 | Critical9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
- EPSS (exploitation in 30 days)
- 1.2% · top 31% of all CVEs (14 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: yes · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.
Affected products
- unaffected 115.20 – ≤ 115.*
- unaffected 128.7 – ≤ 128.*
- unaffected 135 – ≤ *
- unaffected 128.7 – ≤ 128.*
- unaffected 135 – ≤ *
References
References8
- https://bugzilla.mozilla.org/show_bug.cgi?id=1936613 (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-07/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-08/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-09/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-10/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2025-11/ (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/02/msg00006.html (opens in a new tab)
- https://lists.debian.org/debian-lts-announce/2025/02/msg00005.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-2025-1964 (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-2025-1009)Record last updated .