Cyber Posture

CVE-2026-8953

Critical
Microsoft: not affectedMSmacOS: not affectedMacLinux: not affectedLnxMobile: not affectedMobNetwork: not affectedNetApplication: affectedAppOther: not affectedOth

Published: 19 May 2026

Published
19 May 2026
Modified
19 May 2026
KEV Added
—
Patch
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CVSS Score 9.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
EPSS Score 0.0004 13.0th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-8953 is a critical-severity Use After Free (CWE-416) vulnerability in Mozilla Firefox. Its CVSS base score is 9.6 (Critical).

Operationally, ranked at the 13.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SI-16 Memory Protection
addresses: CWE-416

Use-after-free exploits that achieve arbitrary code execution are blocked or significantly hardened by non-executable pages and ASLR.

NVD Description

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)
CWE-416

Affected Products

mozilla
firefox
≤ 115.36.0 · ≤ 151.0.0 · 140.0 — 140.11.0
mozilla
thunderbird
≤ 140.11

References