RHSA-2026:0023 - Security Advisory

Topic

An update for thunderbird is now available for Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support and Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On.

Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

Description

Mozilla Thunderbird is a standalone mail and newsgroup client.

Security Fix(es):

• firefox: Memory safety bugs fixed in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146 (CVE-2025-14333)
• firefox: Use-after-free in the WebRTC: Signaling component (CVE-2025-14321)
• firefox: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2025-14325)
• firefox: Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component (CVE-2025-14322)
• firefox: Privilege escalation in the Netmonitor component (CVE-2025-14328)
• firefox: Privilege escalation in the Netmonitor component (CVE-2025-14329)
• firefox: Same-origin policy bypass in the Request Handling component (CVE-2025-14331)
• firefox: Privilege escalation in the DOM: Notifications component (CVE-2025-14323)
• firefox: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2025-14330)
• firefox: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2025-14324)

For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Solution

For details on how to apply this update, which includes the changes described in this advisory, refer to:

https://access.redhat.com/articles/11258

Affected Products

• Red Hat Enterprise Linux for x86_64 - Extended Update Support Extension 8.4 x86_64
• Red Hat Enterprise Linux Server - AUS 8.4 x86_64

Fixes

• BZ - 2420502 - CVE-2025-14333 firefox: thunderbird: Memory safety bugs fixed in Firefox ESR 140.6, Thunderbird ESR 140.6, Firefox 146 and Thunderbird 146
• BZ - 2420503 - CVE-2025-14321 firefox: thunderbird: Use-after-free in the WebRTC: Signaling component
• BZ - 2420504 - CVE-2025-14325 firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component
• BZ - 2420506 - CVE-2025-14322 firefox: thunderbird: Sandbox escape due to incorrect boundary conditions in the Graphics: CanvasWebGL component
• BZ - 2420508 - CVE-2025-14328 firefox: thunderbird: Privilege escalation in the Netmonitor component
• BZ - 2420509 - CVE-2025-14329 firefox: thunderbird: Privilege escalation in the Netmonitor component
• BZ - 2420512 - CVE-2025-14331 firefox: thunderbird: Same-origin policy bypass in the Request Handling component
• BZ - 2420513 - CVE-2025-14323 firefox: thunderbird: Privilege escalation in the DOM: Notifications component
• BZ - 2420516 - CVE-2025-14330 firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component
• BZ - 2420517 - CVE-2025-14324 firefox: thunderbird: JIT miscompilation in the JavaScript Engine: JIT component

CVEs

• CVE-2025-14321
• CVE-2025-14322
• CVE-2025-14323
• CVE-2025-14324
• CVE-2025-14325
• CVE-2025-14328
• CVE-2025-14329
• CVE-2025-14330
• CVE-2025-14331
• CVE-2025-14333

References

• https://access.redhat.com/security/updates/classification/#important