CVE-2026-117929: Mozilla Firefox · Use-after-free in the DOM: Core & HTML component
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited.
Data as of 27 Oct 2026, 17:24 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Exploitation evidence
Disclosed: evidence found.
CVE published 27 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
AI-suggested
A fix for this vulnerability is available in Firefox 159, Firefox ESR 115.44, and Firefox ESR 153.6. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation steps are required beyond applying the official update.
Description
CVE-2026-117929 is a use-after-free vulnerability in the DOM Core & HTML component of Mozilla Firefox. This security flaw was addressed and fixed in Firefox version 159 and the corresponding Firefox ESR versions 115.44 and 153.6. The vulnerability is considered high impact due to the nature of use-after-free bugs, which can lead to memory corruption and potentially allow attackers to execute arbitrary code or cause crashes.