CVE-2026-117988: Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component
Source GCVE Database
Not known to be exploited.
Data as of 27 Oct 2026, 22:14 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 and has been incorporated in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6. Users and administrators should update to these versions or later to mitigate the risk. No additional mitigation steps are indicated by the vendor advisory.
Description
CVE-2026-117988 is a sandbox escape vulnerability caused by incorrect boundary conditions in the Graphics: CanvasWebGL component. This flaw allows an attacker to break out of the sandbox environment. The issue was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
References
- nvd.nist.gov/vuln/detail/CVE-2026-117988 (opens in a new tab)
- bugzilla.mozilla.org/show_bug.cgi?id=2079072 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-118 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-120 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-121 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-122 (opens in a new tab)