Critical 9.8Published Jan 13, 2026

CVE-2026-0892Memory safety bugs fixed in Firefox 147 and Thunderbird 147

Updated under an hour ago (Oct 26, 2026, 4:10 AM ET)

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It affects Mozilla Firefox and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for Mozilla Firefox

Exploited in the last 30 days

Memory safety bugs present in Firefox 146 and Thunderbird 146. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could have been exploited to run arbitrary code. This vulnerability was fixed in Firefox 147 and Thunderbird 147.

CVSS: 9.8 CRITICAL (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Weakness (CWE): CWE-119
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: mozilla
NVD analysis: Modified
Record last updated: Apr 13, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Mozilla Firefox mozilla:firefox (from the name)	from 147 not affected	CNA record
Mozilla Thunderbird mozilla:thunderbird (from the name)	from 147 not affected	CNA record
mozilla firefox mozilla:firefox	before 147.0	NVD
mozilla thunderbird mozilla:thunderbird	before 147.0	NVD

References

https://bugzilla.mozilla.org/buglist.cgi?bug_id=1986912%2C1996718%2C1999633%2C2001081%2C2004443broken-link
https://www.mozilla.org/security/advisories/mfsa2026-01/vendor-advisory
https://www.mozilla.org/security/advisories/mfsa2026-04/vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.