CVE-2026-117881: Mozilla Firefox

Use-after-free in the DOM: Core & HTML component

CVSS 8.8 HighEPSS 0.0040 · 34th percentile

Published by the CVE Program (CNA: mozilla) at 27 Oct 2026, 14:05 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. This CVE names a vendor and product rather than a package, so the lockfile check doesn’t match it.

Affected products, as the CNA wrote them
Vendor	Product	Versions
Mozilla	Firefox	unaffected 115.44 to 115., inclusive rpm unaffected 153.6 to 153., inclusive rpm unaffected 159 to *, inclusive rpm
Mozilla	Thunderbird	unaffected 153.6 to 153., inclusive rpm unaffected 159 to , inclusive rpm

Identifiers

CVE-2026-117881

CNA

mozilla

Weakness (CWE)

CWE-416

Not analysed yet

We haven’t published our own analysis of this CVE. If a person reviews it, this page will say what’s affected and what has to be true for it to matter.

Severity and exploitation

Score	Rating	CVSS	Vector	Source
8.8	High	3.1	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	ADP (CISA-ADP)

CISA KEV Not listed.
EPSS 0.0040, the 34th percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

Timeline

27 Oct 2026, 14:05 UTC Confirmed by the CVE List
27 Oct 2026, 14:16 UTC Confirmed by NVD

Sources

References from the CNA

Facts on this page come from the CVE List as the CNA published them, with CVSS from the sources named above, CISA KEV and FIRST EPSS. Vendors, products and versions are shown as the CNA wrote them. We don’t reproduce the CVE’s description.