Red Hat Security Advisory: thunderbird security update
Multiple security vulnerabilities affecting Mozilla Thunderbird and related components have been addressed in Red Hat Enterprise Linux 8.4 updates. 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 in Thunderbird and Firefox ESR versions, and an integer overflow in the graphics text component. The update fixes these issues in Thunderbird ESR 140.9.1 and Firefox 149.0.2 among others.
AI Analysis
Technical Summary
This Red Hat security advisory addresses several vulnerabilities impacting Mozilla Thunderbird and associated libraries on Red Hat Enterprise Linux 8.4. The issues include a use-after-free vulnerability in libpng (CVE-2026-33416) that could lead to arbitrary code execution, out-of-bounds read/write in libpng's Neon palette expansion causing information disclosure and denial of service (CVE-2026-33636), multiple memory safety bugs fixed in Thunderbird ESR 140.9.1 and Firefox 149.0.2 (CVE-2026-5731, CVE-2026-5734), and an integer overflow in the graphics text component affecting both Firefox and Thunderbird (CVE-2026-5732). These vulnerabilities are addressed by updated packages provided by Red Hat for affected versions of Thunderbird and Firefox ESR.
Potential Impact
The vulnerabilities collectively could allow an attacker to execute arbitrary code, cause denial of service, or disclose sensitive information via crafted inputs to Thunderbird or its underlying libraries. Memory safety bugs and integer overflow issues increase the risk of crashes or exploitation. The advisory rates the security impact as Important (high severity), indicating significant risk if unpatched.
Mitigation Recommendations
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 8.4 that address these vulnerabilities. Users should apply the security update RHSA-2026:14303 promptly to remediate these issues. Detailed update instructions are available at https://access.redhat.com/articles/11258. No additional mitigations are specified or required beyond applying the official update.
Red Hat Security Advisory: thunderbird security update
Description
Multiple security vulnerabilities affecting Mozilla Thunderbird and related components have been addressed in Red Hat Enterprise Linux 8.4 updates. 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 in Thunderbird and Firefox ESR versions, and an integer overflow in the graphics text component. The update fixes these issues in Thunderbird ESR 140.9.1 and Firefox 149.0.2 among others.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This Red Hat security advisory addresses several vulnerabilities impacting Mozilla Thunderbird and associated libraries on Red Hat Enterprise Linux 8.4. The issues include a use-after-free vulnerability in libpng (CVE-2026-33416) that could lead to arbitrary code execution, out-of-bounds read/write in libpng's Neon palette expansion causing information disclosure and denial of service (CVE-2026-33636), multiple memory safety bugs fixed in Thunderbird ESR 140.9.1 and Firefox 149.0.2 (CVE-2026-5731, CVE-2026-5734), and an integer overflow in the graphics text component affecting both Firefox and Thunderbird (CVE-2026-5732). These vulnerabilities are addressed by updated packages provided by Red Hat for affected versions of Thunderbird and Firefox ESR.
Potential Impact
The vulnerabilities collectively could allow an attacker to execute arbitrary code, cause denial of service, or disclose sensitive information via crafted inputs to Thunderbird or its underlying libraries. Memory safety bugs and integer overflow issues increase the risk of crashes or exploitation. The advisory rates the security impact as Important (high severity), indicating significant risk if unpatched.
Mitigation Recommendations
Red Hat has released updated Thunderbird packages for Red Hat Enterprise Linux 8.4 that address these vulnerabilities. Users should apply the security update RHSA-2026:14303 promptly to remediate these issues. Detailed update instructions are available at https://access.redhat.com/articles/11258. No additional mitigations are specified or required 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-2026:14303
- Cve Count
- 5
- Additional Cves
- ["CVE-2026-5732","CVE-2026-5734","CVE-2026-33416","CVE-2026-33636"]
- Cvss Version
- null
Threat ID: 6a16097ee29bf47b5064afd2
Added to database: 05/26/2026, 20:58:38 UTC
Last enriched: 07/23/2026, 00:50:54 UTC
Last updated: 07/31/2026, 19:22:59 UTC
Views: 54
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