RHSA-2025:0080 — Security Advisory

An update for firefox is now available for Red Hat Enterprise Linux 9.

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.