What is CVE-2026-100805?

CVE-2026-100805 is a high-severity vulnerability, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.5/10. Published 2026-09-29.

How severe is CVE-2026-100805?

High severity. CVSS v3 base score is 7.5 out of 10.

CVE-2026-100805

CVE-2026-100805

Race condition, use-after-free in the Audio/Video component. This vulnerability was fixed in Firefox 157.

Vulnerability class: Race Condition

Published 2026-09-29 · last modified 2026-09-30.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)
CWE-416 — Use After Free

References

bugzilla.mozilla.org/show_bug.cgi
www.mozilla.org/security/advisories/mfsa2026-97/

Frequently asked questions

What is CVE-2026-100805?: CVE-2026-100805 is a high-severity vulnerability, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.5/10. Published 2026-09-29.
How severe is CVE-2026-100805?: High severity. CVSS v3 base score is 7.5 out of 10.