Mozilla Thunderbird is a standalone mail and newsgroup client. Security Fix(es): * libexpat: denial of service via crafted XML input (CVE-2026-45186) * firefox: Mitigation bypass in the Enterprise Policies component (CVE-2026-109764) * firefox: Spoofing issue in the DOM: Web Serial component (CVE-2026-109770) * firefox: Mitigation bypass in the File Handling component (CVE-2026-109783) * firefox: thunderbird: Privilege escalation in the Application Update component (CVE-2026-109704) * firefox: Use-after-free in the XML component (CVE-2026-109718) * firefox: Information disclosure in the PDF Viewer component (CVE-2026-109742) * firefox: Incorrect boundary conditions in the JavaScript Engine component (CVE-2026-109715) * firefox: firefox: Sandbox escape via incorrect boundary conditions in Win32 widget (CVE-2026-109740) * firefox: Use-after-free in the Storage: IndexedDB component (CVE-2026-109706) * firefox: Use-after-free in the Crash Reporting component (CVE-2026-109713) * firefox: Use-after-free in the DOM: Core & HTML component (CVE-2026-109724) * firefox: Sandbox escape due to uninitialized memory in the DOM: Web Serial component (CVE-2026-109745) * firefox: Mitigation bypass in the File Handling component (CVE-2026-109782) * firefox: Information disclosure, privilege escalation in the Security: Process Sandboxing component (CVE-2026-109709) * firefox: Sandbox escape, site isolation issue due to incorrect boundary conditions, use-after-free in the Networking component (CVE-2026-109705) * firefox: Use-after-free in the Audio/Video: Playback component (CVE-2026-109738) * firefox: Sandbox escape due to race condition in the Networking component (CVE-2026-109757) * firefox: Use-after-free in the Storage: Bucket File System component (CVE-2026-109741) * firefox: Use-after-free in the JavaScript Engine: JIT component (CVE-2026-109729) * firefox: Other issue in the DOM: File component (CVE-2026-109744) * firefox: Incorrect boundary conditions in the JavaScript Engine component (CVE-2026-109716) * firefox: Race condition, use-after-free in the Graphics: CanvasWebGL component (CVE-2026-109719) * firefox: Incorrect boundary conditions in the Layout component (CVE-2026-109753) * firefox: Integer overflow in the Layout: Text and Fonts component (CVE-2026-109723) * firefox: Privilege escalation in the DOM: Navigation component (CVE-2026-109756) * firefox: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2026-109733) * firefox: thunderbird: Mitigation bypass in the DOM: Security component (CVE-2026-109734) * firefox: Mitigation bypass in the File Handling component (CVE-2026-109763) * firefox: Sandbox escape due to incorrect boundary conditions in the Networking component (CVE-2026-109708) * firefox: Use-after-free in the DOM: Bindings (WebIDL) component (CVE-2026-109717) * firefox: Use-after-free in the DOM: Workers component (CVE-2026-109752) * firefox: Race condition in the XPCOM component (CVE-2026-109776) * firefox: Sandbox escape due to use-after-free in the Networking component (CVE-2026-109707) * firefox: Mitigation bypass in the Networking: HTTP component (CVE-2026-109760) * firefox: JIT miscompilation in the JavaScript: WebAssembly component (CVE-2026-109720) * firefox: Information disclosure in the Storage: IndexedDB component (CVE-2026-109777) * firefox: Use-after-free in the SVG component (CVE-2026-109726) * firefox: Integer overflow in the Graphics component (CVE-2026-109730) * firefox: Use-after-free in the Audio/Video component (CVE-2026-109727) * firefox: Mitigation bypass in the Enterprise Policies component (CVE-2026-109737) * firefox: Mitigation bypass in the Enterprise Policies component (CVE-2026-109766) * firefox: Use-after-free in the DOM: Streams component (CVE-2026-109732) * firefox: Site isolation issue in the Networking component (CVE-2026-109759) * firefox: Privilege escalation in the WebExtensions component (CVE-2026-109778) * firefox: Incorrect boundary conditions in the SVG component (CVE-2026-109762) * firefox: Race condition, use-after-free in the Graphics: Text component (CVE-2026-109765) * firefox: Incorrect boundary conditions in the DOM: Editor component (CVE-2026-109754) * firefox: Information disclosure in the Networking component (CVE-2026-109751) * firefox: Use-after-free in the DOM: Core & HTML component (CVE-2026-109725) * firefox: Sandbox escape due to uninitialized memory in the Graphics component (CVE-2026-109712) * firefox: Use-after-free in the Graphics: Canvas2D component (CVE-2026-109711) * firefox: Frame poisoning in the Layout component (CVE-2026-109736) * firefox: JIT miscompilation in the JavaScript Engine: JIT component (CVE-2026-109722) * firefox: Information disclosure in the Networking component (CVE-2026-109767) * firefox: Denial-of-service in the WebRTC component (CVE-2026-109775) * firefox: Use-after-free in the DOM: Animation component (CVE-2026-109728) * firefox: Denial-of-service in the Printing: Output component (CVE-2026-109781) * firefox: thunderbird: Use-after-free in the Graphics: Text component (CVE-2026-109710) * firefox: thunderbird: Incorrect boundary conditions in the Graphics: Canvas2D component (CVE-2026-109731) * firefox: Incorrect boundary conditions in the JavaScript Engine: JIT component (CVE-2026-109721) * firefox: Privilege escalation in the Panning and Zooming component (CVE-2026-109743) Bug Fix(es) and Enhancement(s): * Thunderbird ESR 153 rebase [rhel-9.8.z] (JIRA:RHEL-175199) 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.