- 4.3MediumCVSS base score
- 0.25%Exploitation in 30 daysEPSS · top 83% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
Information disclosure in the Networking: JAR component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.
Timeline
ID reserved
By mozilla
- 3 days later
· 3 days later
Published
- 1 day later
· 1 day 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 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
| NVDNVD · Analyzed | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N |
- EPSS (exploitation in 30 days)
- 0.25% · top 83% of all CVEs (10 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
Loading the EPSS history…
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Affected products
- unaffected 115.42 – ≤ 115.*
- unaffected 140.17 – ≤ 140.*
- unaffected 153.4 – ≤ 153.*
- unaffected 157 – ≤ *
- unaffected 140.17 – ≤ 140.*
- unaffected 153.4 – ≤ 153.*
- unaffected 157 – ≤ *
References
8
- https://bugzilla.mozilla.org/show_bug.cgi?id=2061526 (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-100/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-101/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-102/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-103/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-97/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-98/ (opens in a new tab)
- https://www.mozilla.org/security/advisories/mfsa2026-99/ (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-2026-88918 (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-2026-100766)Record last updated .