An update for firefox is now available for Red Hat Enterprise Linux 8.4
 Advanced Mission Critical Update Support, Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions, and Red Hat Enterprise Linux 8.4 Telecommunications Update Service.

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.

Mozilla Firefox is an open-source web browser, designed for standards
 compliance, performance, and portability.

Security Fix(es):

* firefox: Use-after-free when breaking lines in text (CVE-2025-0238)

* firefox: Memory corruption when using JavaScript Text Segmentation
 (CVE-2025-0241)

* firefox: Alt-Svc ALPN validation failure when redirected (CVE-2025-0239)

* firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird
 134, Firefox ESR 128.6, and Thunderbird 128.6 (CVE-2025-0243)

* firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird
 134, Firefox ESR 115.19, Firefox ESR 128.6, Thunderbird 115.19, and Thunderbird 128.6 (CVE-2025-0242)

* firefox: WebChannel APIs susceptible to confused deputy attack
 (CVE-2025-0237)

* firefox: Compartment mismatch when parsing JavaScript JSON module
 (CVE-2025-0240)

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.

This content is licensed under the Creative Commons Attribution 4.0 International License (https://creativecommons.org/licenses/by/4.0/). If you distribute this content, or a modified version of it, you must provide attribution to Red Hat Inc. and provide a link to the original.

CVE-2025-0237: Unintended Proxy or Intermediary ('Confused Deputy')
 (CWE-441)
CVE-2025-0238: Use After Free (CWE-416)
CVE-2025-0239: URL Redirection to Untrusted Site ('Open Redirect')
 (CWE-601)
CVE-2025-0240: Use After Free (CWE-416)
CVE-2025-0241: Improper Restriction of Operations within the Bounds of a Memory
 Buffer (CWE-119)
CVE-2025-0242: Buffer Copy without Checking Size of Input ('Classic Buffer
 Overflow') (CWE-120)
CVE-2025-0243: Buffer Copy without Checking Size of Input ('Classic Buffer
 Overflow') (CWE-120)