CVE-2026-100766CWE-200information-disclosure

CVE-2026-100766

Medium · published September 29, 2026

CVSS v3.1
4.3
EPSS
0%
Percentile
15.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
4.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
CVSS v4.0
Not supplied
EPSS
0.00251 · 15.6th percentile
Weakness
CWE-200 · Exposure of Sensitive Information to an Unauthorized Actor
Published
2026-09-29T17:17Z
Affected products (7)
ProductVersionsFixed in
mozilla/firefox< 115.42.0115.42.0
mozilla/firefox≥ 116.0.0, < 140.17.0140.17.0
mozilla/firefox≥ 141.0.0, < 153.4.0153.4.0
mozilla/firefox≥ 154.0.0, < 157.0.0157.0.0
mozilla/thunderbird< 140.17.0140.17.0
mozilla/thunderbird≥ 141.0, < 153.4.0153.4.0
mozilla/thunderbird≥ 154.0, < 157.0157.0
References (8)
https://bugzilla.mozilla.org/show_bug.cgi?id=2061526 · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-100/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-101/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-102/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-103/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-97/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-98/ · [email protected]https://www.mozilla.org/security/advisories/mfsa2026-99/ · [email protected]
EPSS history
Timeline
  • 01 OCT 03:44Z
    EPSS moved — → 0%
    epss
  • 29 SEP 12:35Z
    Information disclosure in the Networking: JAR component
    cvelistv5