Red Hat Security Advisory: thunderbird security update
Mozilla Thunderbird is a standalone mail and newsgroup client. Security Fix(es): * firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-8388) * firefox: Other issue in the JavaScript Engine component (CVE-2026-8391) * firefox: Sandbox escape in the Profile Backup component (CVE-2026-8401) * firefox: Integer overflow in the Networking: JAR component (CVE-2026-8956) * firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 (CVE-2026-8975) * firefox: Privilege escalation in the DOM: Workers component (CVE-2026-8955) * firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component (CVE-2026-8968) * firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component (CVE-2026-8954) * firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component (CVE-2026-8958) * firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component (CVE-2026-8946) * firefox: Privilege escalation in the Security component (CVE-2026-8970) * firefox: Same-origin policy bypass in the Networking: HTTP component (CVE-2026-8950) * firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 (CVE-2026-8974) * firefox: Sandbox escape due to use-after-free in the Disability Access APIs component (CVE-2026-8953) * firefox: Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component (CVE-2026-8959) * firefox: Spoofing issue in the Form Autofill component (CVE-2026-8961) * firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-8947) * firefox: Mitigation bypass in the DOM: Security component (CVE-2026-8962) * firefox: Privilege escalation in the Enterprise Policies component (CVE-2026-8957) 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.
Red Hat Security Advisory: thunderbird security update
Description
Mozilla Thunderbird is a standalone mail and newsgroup client. Security Fix(es): * firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-8388) * firefox: Other issue in the JavaScript Engine component (CVE-2026-8391) * firefox: Sandbox escape in the Profile Backup component (CVE-2026-8401) * firefox: Integer overflow in the Networking: JAR component (CVE-2026-8956) * firefox: Memory safety bugs fixed in Firefox ESR 115.36, Firefox ESR 140.11 and Firefox 151 (CVE-2026-8975) * firefox: Privilege escalation in the DOM: Workers component (CVE-2026-8955) * firefox: Denial-of-service due to invalid pointer in the Audio/Video: Web Codecs component (CVE-2026-8968) * firefox: Incorrect boundary conditions, integer overflow in the Audio/Video component (CVE-2026-8954) * firefox: Information disclosure, sandbox escape in the Security: Process Sandboxing component (CVE-2026-8958) * firefox: Incorrect boundary conditions in the Audio/Video: Web Codecs component (CVE-2026-8946) * firefox: Privilege escalation in the Security component (CVE-2026-8970) * firefox: Same-origin policy bypass in the Networking: HTTP component (CVE-2026-8950) * firefox: Memory safety bugs fixed in Firefox ESR 140.11 and Firefox 151 (CVE-2026-8974) * firefox: Sandbox escape due to use-after-free in the Disability Access APIs component (CVE-2026-8953) * firefox: Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component (CVE-2026-8959) * firefox: Spoofing issue in the Form Autofill component (CVE-2026-8961) * firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-8947) * firefox: Mitigation bypass in the DOM: Security component (CVE-2026-8962) * firefox: Privilege escalation in the Enterprise Policies component (CVE-2026-8957) 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.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:21381
- Cve Count
- 19
- Additional Cves
- ["CVE-2026-8391","CVE-2026-8401","CVE-2026-8946","CVE-2026-8947","CVE-2026-8950","CVE-2026-8953","CVE-2026-8954","CVE-2026-8955","CVE-2026-8956","CVE-2026-8957","CVE-2026-8958","CVE-2026-8959","CVE-2026-8961","CVE-2026-8962","CVE-2026-8968","CVE-2026-8970","CVE-2026-8974","CVE-2026-8975"]
- Cvss Version
- null
Threat ID: 6a175ed2e29bf47b50ed886b
Added to database: 5/27/2026, 9:14:58 PM
Last updated: 5/27/2026, 9:15:05 PM
Views: 1
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