by Kastro
Paper/Archive/CVE-2026-117862

CVE-2026-117862

Mozilla Firefox — Privilege escalation due to incorrect boundary conditions in the Networking component

EPSS 0.2%CVSS 9.8
critical.is priorityof 100
31
CVSS 9.8 (ADP)9.8 / 10 × 3029.4Not in CISA KEV+300.0EPSS percentile 8.4.084 × 201.7No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

Privilege escalation due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.

Affected

ProductAffectedFixed inSource
Firefoxsee advisory115.44CNA
Thunderbirdsee advisory153.6CNA

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: yes · Technical impact: total

References

refbugzilla.mozilla.org/show_bug.cgi?id=2054644refmozilla.org/security/advisories/mfsa2026-118refmozilla.org/security/advisories/mfsa2026-119refmozilla.org/security/advisories/mfsa2026-120refmozilla.org/security/advisories/mfsa2026-121refmozilla.org/security/advisories/mfsa2026-122