CVE-2026-100760: Mozilla Firefox · CWE-693
Affects Mozilla FirefoxSource CVE Database V5
Not known to be exploited · CVSS 9.6 Critical · fixed in 153.4 : patch Mozilla Firefox as a priority.
Data as of 12 Nov 2026, 23:24 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 23% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 153.4
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 13 Nov 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Mozilla Firefox | Affected
| Fixed in
|
AI-suggested
Users and administrators should update affected Mozilla products to Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, or Firefox 157 or later versions where the vulnerability is fixed. No other mitigation is indicated by the vendor advisories.
Description
CVE-2026-100760 is a critical sandbox escape vulnerability in Mozilla Firefox's process sandboxing component. It allows an attacker to break out of the sandbox, potentially leading to full system compromise. The flaw was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.
References
- bugzilla.mozilla.org/show_bug.cgi?id=2058017 (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-100/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-97/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-101/ (opens in a new tab)
- mozilla.org/security/advisories/mfsa2026-103/ (opens in a new tab)