CVE-2026-117899 Affecting firefox package, versions <159.0-1
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published28 Oct 2026
- disclosed27 Oct 2026
Introduced: 27 Oct 2026
NewCVE-2026-117899 (opens in a new tab)How to fix?
Upgrade Debian:unstable firefox to version 159.0-1 or higher.
NVD Description
Note: Versions mentioned in the description apply only to the upstream firefox package and not the firefox package as distributed by Debian.
See How to fix? for Debian:unstable relevant fixed versions and status.
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
References
- https://security-tracker.debian.org/tracker/CVE-2026-117899
- https://bugzilla.mozilla.org/show_bug.cgi?id=2079046
- https://www.mozilla.org/security/advisories/mfsa2026-118/
- https://www.mozilla.org/security/advisories/mfsa2026-119/
- https://www.mozilla.org/security/advisories/mfsa2026-120/
- https://www.mozilla.org/security/advisories/mfsa2026-121/
- https://www.mozilla.org/security/advisories/mfsa2026-122/