CVE-2026-0891

high Red Hat
CVSS v3 Base Score
7.5
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS Score
0.0%
Exploitation probability in 30 days
Top 94% most likely to be exploited
Attack Characteristics
Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Published: January 13, 2026 (121 days ago)
Last Modified: January 13, 2026
Vendor: Red Hat
Fix Available: ✓ Yes

Description

Memory safety bugs present in Firefox ESR 140.6, Thunderbird ESR 140.6, 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, Firefox ESR < 140.7, Thunderbird < 147, and Thunderbird < 140.7.

Affected Products

Red Hat Enterprise Linux 10Red Hat Enterprise Linux 6Red Hat Enterprise Linux 7Red Hat Enterprise Linux 10.0 Extended Update SupportRed Hat Enterprise Linux 7 Extended Lifecycle SupportRed Hat Enterprise Linux 8Red Hat Enterprise Linux 8.2 Advanced Update SupportRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update SupportRed Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-OnRed Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

Fix Status

✅ Fix Available

References

🔗 bugzilla.redhat.com 🔗 www.cve.org 🔗 nvd.nist.gov 🔗 www.mozilla.org 🔗 www.mozilla.org