RHSA-2025:0135 - Security Advisory

Topic

An update for firefox is now available for Red Hat Enterprise Linux 9.4 Extended Update Support.

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 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.

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 9.4 x86_64
• Red Hat Enterprise Linux Server - AUS 9.4 x86_64
• Red Hat Enterprise Linux for IBM z Systems - Extended Update Support 9.4 s390x
• Red Hat Enterprise Linux for Power, little endian - Extended Update Support 9.4 ppc64le
• Red Hat Enterprise Linux for ARM 64 - Extended Update Support 9.4 aarch64
• Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions 9.4 ppc64le
• Red Hat Enterprise Linux for x86_64 - Update Services for SAP Solutions 9.4 x86_64
• Red Hat Enterprise Linux for ARM 64 - 4 years of updates 9.4 aarch64
• Red Hat Enterprise Linux for IBM z Systems - 4 years of updates 9.4 s390x

Fixes

• BZ - 2336165 - CVE-2025-0238 firefox: Use-after-free when breaking lines in text
• BZ - 2336168 - CVE-2025-0241 firefox: Memory corruption when using JavaScript Text Segmentation
• BZ - 2336170 - CVE-2025-0239 firefox: Alt-Svc ALPN validation failure when redirected
• BZ - 2336175 - CVE-2025-0243 firefox: thunderbird: Memory safety bugs fixed in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6
• BZ - 2336181 - CVE-2025-0242 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
• BZ - 2336182 - CVE-2025-0237 firefox: WebChannel APIs susceptible to confused deputy attack
• BZ - 2336188 - CVE-2025-0240 firefox: Compartment mismatch when parsing JavaScript JSON module

CVEs

• CVE-2025-0237
• CVE-2025-0238
• CVE-2025-0239
• CVE-2025-0240
• CVE-2025-0241
• CVE-2025-0242
• CVE-2025-0243

References

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