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.
Affected products
mozilla: firefox; mozilla: thunderbird
References8
- www.mozilla.org/security/advisories/mfsa2026-100/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-101/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-102/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-103/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-97/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-98/ Vendor Advisory
- www.mozilla.org/security/advisories/mfsa2026-99/ Vendor Advisory
- bugzilla.mozilla.org/show_bug.cgi?id=2061526 Permissions Required
Metrics
- CVSS 3.1
-
4.3
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N - EPSS — exploit probability
- 0% percentile: 17 · as of 10 November 2026
- CWE
- CWE-200
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