Important: thunderbird security update
Mozilla Thunderbird is a standalone mail and newsgroup client. 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.
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
Mozilla Thunderbird is a standalone mail and newsgroup client. 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.
05 / REFERENCES
Further evidence
- https://access.redhat.com/errata/RHSA-2026:9638
- https://access.redhat.com/security/cve/CVE-2026-33416
- https://access.redhat.com/security/cve/CVE-2026-33636
- https://access.redhat.com/security/cve/CVE-2026-5731
- https://access.redhat.com/security/cve/CVE-2026-5732
- https://access.redhat.com/security/cve/CVE-2026-5734
- https://bugzilla.redhat.com/2451805
- https://bugzilla.redhat.com/2451819
- https://bugzilla.redhat.com/2455897
- https://bugzilla.redhat.com/2455901
- https://bugzilla.redhat.com/2455908
- https://errata.almalinux.org/10/ALSA-2026-9638.html