Red Hat Security Advisory: firefox security update
Multiple security vulnerabilities affecting Mozilla Firefox and related components have been addressed in Red Hat Enterprise Linux 7 Extended Lifecycle Support. These include arbitrary code execution due to a use-after-free in libpng, information disclosure and denial of service via out-of-bounds read/write in libpng's Neon palette expansion, memory safety bugs, and an integer overflow in the Graphics: Text component. The update fixes these issues in Firefox ESR 140.9.1 and related Thunderbird versions. The vulnerabilities have been rated with an important security impact by Red Hat.
AI Analysis
Technical Summary
This advisory covers several security fixes in Mozilla Firefox and related components distributed with Red Hat Enterprise Linux 7 Extended Lifecycle Support. The vulnerabilities include CVE-2026-33416, a use-after-free in libpng leading to arbitrary code execution; CVE-2026-33636, an out-of-bounds read/write in libpng causing information disclosure and denial of service; CVE-2026-5734 and CVE-2026-5731, memory safety bugs fixed in Firefox ESR 140.9.1 and Thunderbird ESR 140.9.1; and CVE-2026-5732, an integer overflow in the Graphics: Text component. These issues affect Firefox ESR 140.9.1 and related Thunderbird versions on Red Hat Enterprise Linux 7 ELS. The Red Hat advisory RHSA-2026:13977 provides details and updates for affected packages.
Potential Impact
The vulnerabilities include arbitrary code execution, information disclosure, denial of service, and memory safety issues in Firefox and related components. Exploitation could allow attackers to execute code, cause application crashes, or leak sensitive information. The security impact is rated as Important by Red Hat, indicating a high risk to affected systems if unpatched.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 7 Extended Lifecycle Support that address these vulnerabilities. Users should apply the Firefox update (version 140.9.1-2.el7_9 and related) as provided in advisory RHSA-2026:13977. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official update.
Red Hat Security Advisory: firefox security update
Description
Multiple security vulnerabilities affecting Mozilla Firefox and related components have been addressed in Red Hat Enterprise Linux 7 Extended Lifecycle Support. These include arbitrary code execution due to a use-after-free in libpng, information disclosure and denial of service via out-of-bounds read/write in libpng's Neon palette expansion, memory safety bugs, and an integer overflow in the Graphics: Text component. The update fixes these issues in Firefox ESR 140.9.1 and related Thunderbird versions. The vulnerabilities have been rated with an important security impact by Red Hat.
Affected software
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AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This advisory covers several security fixes in Mozilla Firefox and related components distributed with Red Hat Enterprise Linux 7 Extended Lifecycle Support. The vulnerabilities include CVE-2026-33416, a use-after-free in libpng leading to arbitrary code execution; CVE-2026-33636, an out-of-bounds read/write in libpng causing information disclosure and denial of service; CVE-2026-5734 and CVE-2026-5731, memory safety bugs fixed in Firefox ESR 140.9.1 and Thunderbird ESR 140.9.1; and CVE-2026-5732, an integer overflow in the Graphics: Text component. These issues affect Firefox ESR 140.9.1 and related Thunderbird versions on Red Hat Enterprise Linux 7 ELS. The Red Hat advisory RHSA-2026:13977 provides details and updates for affected packages.
Potential Impact
The vulnerabilities include arbitrary code execution, information disclosure, denial of service, and memory safety issues in Firefox and related components. Exploitation could allow attackers to execute code, cause application crashes, or leak sensitive information. The security impact is rated as Important by Red Hat, indicating a high risk to affected systems if unpatched.
Mitigation Recommendations
Red Hat has released updated Firefox packages for Red Hat Enterprise Linux 7 Extended Lifecycle Support that address these vulnerabilities. Users should apply the Firefox update (version 140.9.1-2.el7_9 and related) as provided in advisory RHSA-2026:13977. For detailed update instructions, refer to https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official update.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:13977
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-5732","CVE-2026-5734","CVE-2026-33416","CVE-2026-33636"]
- Cvss Version
- null
Threat ID: 6a160983e29bf47b506501b5
Added to database: 05/26/2026, 20:58:43 UTC
Last enriched: 07/23/2026, 00:53:41 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 60
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