CVE-2026-0892

EUVD-2026-2358
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 affects Firefox < 147 and Thunderbird < 147.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
9.8 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA-ADPADP
9.8 CRITICAL
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base Score
CVSS 3.x
EPSS Score
Percentile: 5%
Affected Products (NVD)
VendorProductVersion
mozillafirefox
𝑥
< 147.0
mozillathunderbird
𝑥
< 147.0
𝑥
= Vulnerable software versions
Debian logo
Debian Releases
Debian Product
Codename
firefox
sid
148.0-1
fixed
Common Weakness Enumeration
References
https://bugzilla.mozilla.org/buglist.cgi?bug_id=1986912%2C1996718%2C1999633%2C2001081%2C2004443
https://www.mozilla.org/security/advisories/mfsa2026-01/
https://www.mozilla.org/security/advisories/mfsa2026-04/