Red Hat Security Advisory: firefox security update
Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability. Security Fix(es): * libpng: libpng: Arbitrary code execution due to use-after-free vulnerability (CVE-2026-33416) * libpng: libpng: Information disclosure and denial of service via out-of-bounds read/write in Neon palette expansion (CVE-2026-33636) * thunderbird: firefox: Memory safety bugs fixed in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2 and Thunderbird 149.0.2 (CVE-2026-5734) * thunderbird: firefox: Memory safety bugs fixed in Firefox ESR 115.34.1, Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2 and Thunderbird 149.0.2 (CVE-2026-5731) * firefox: thunderbird: Incorrect boundary conditions, integer overflow in the Graphics: Text component (CVE-2026-5732) 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.
AI Analysis
Technical Summary
This Red Hat security advisory addresses multiple vulnerabilities affecting Mozilla Firefox and Thunderbird, including CVE-2026-33416 (libpng use-after-free leading to arbitrary code execution), CVE-2026-33636 (libpng out-of-bounds read/write causing information disclosure and denial of service), CVE-2026-5731 and CVE-2026-5734 (memory safety bugs), and CVE-2026-5732 (integer overflow in the graphics text component). These issues are fixed in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2, and Thunderbird 149.0.2. The advisory covers Red Hat Enterprise Linux 10 and its extended update support versions across multiple architectures. The vendor has released patches to address these vulnerabilities.
Potential Impact
The vulnerabilities include arbitrary code execution, information disclosure, denial of service, memory safety issues, and integer overflow, which could allow an attacker to execute code, cause application crashes, or leak sensitive information. These issues affect Firefox and Thunderbird versions prior to the fixed releases. The security impact is rated as Important (high severity) by Red Hat Product Security.
Mitigation Recommendations
A patch is available and should be applied promptly. The update to Firefox ESR 140.9.1 and Thunderbird ESR 140.9.1 or later versions (including Firefox 149.0.2 and Thunderbird 149.0.2) resolves these vulnerabilities. Refer to the Red Hat advisory RHSA-2026:7672 and the update instructions at https://access.redhat.com/articles/11258 for detailed remediation steps.
Red Hat Security Advisory: firefox security update
Description
Mozilla Firefox is an open-source web browser, designed for standards compliance, performance, and portability. Security Fix(es): * libpng: libpng: Arbitrary code execution due to use-after-free vulnerability (CVE-2026-33416) * libpng: libpng: Information disclosure and denial of service via out-of-bounds read/write in Neon palette expansion (CVE-2026-33636) * thunderbird: firefox: Memory safety bugs fixed in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2 and Thunderbird 149.0.2 (CVE-2026-5734) * thunderbird: firefox: Memory safety bugs fixed in Firefox ESR 115.34.1, Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2 and Thunderbird 149.0.2 (CVE-2026-5731) * firefox: thunderbird: Incorrect boundary conditions, integer overflow in the Graphics: Text component (CVE-2026-5732) 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.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses multiple vulnerabilities affecting Mozilla Firefox and Thunderbird, including CVE-2026-33416 (libpng use-after-free leading to arbitrary code execution), CVE-2026-33636 (libpng out-of-bounds read/write causing information disclosure and denial of service), CVE-2026-5731 and CVE-2026-5734 (memory safety bugs), and CVE-2026-5732 (integer overflow in the graphics text component). These issues are fixed in Firefox ESR 140.9.1, Thunderbird ESR 140.9.1, Firefox 149.0.2, and Thunderbird 149.0.2. The advisory covers Red Hat Enterprise Linux 10 and its extended update support versions across multiple architectures. The vendor has released patches to address these vulnerabilities.
Potential Impact
The vulnerabilities include arbitrary code execution, information disclosure, denial of service, memory safety issues, and integer overflow, which could allow an attacker to execute code, cause application crashes, or leak sensitive information. These issues affect Firefox and Thunderbird versions prior to the fixed releases. The security impact is rated as Important (high severity) by Red Hat Product Security.
Mitigation Recommendations
A patch is available and should be applied promptly. The update to Firefox ESR 140.9.1 and Thunderbird ESR 140.9.1 or later versions (including Firefox 149.0.2 and Thunderbird 149.0.2) resolves these vulnerabilities. Refer to the Red Hat advisory RHSA-2026:7672 and the update instructions at https://access.redhat.com/articles/11258 for detailed remediation steps.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:7672
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-5732","CVE-2026-5734","CVE-2026-33416","CVE-2026-33636"]
- State
- PUBLISHED
Threat ID: 6a160984e29bf47b50650e82
Added to database: 05/26/2026, 20:58:44 UTC
Last enriched: 08/05/2026, 18:05:11 UTC
Last updated: 09/13/2026, 22:01:35 UTC
Views: 88
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