update to 140.13.0 ESR (MFSA 2026-72; includes MFSA 2026-64 / 140.12.1 fixes)
CVE-2026-14899: The code to parse MIME headers for display when forwarding
a message (if the setting to view all headers was enabled) had an
off-by-one error, allowing a single byte to be read from the memory after
the buffer for the headers, and potentially crashing Thunderbird
CVE-2026-15718: Invalid pointer in the JavaScript: WebAssembly component.
Exploit code for this issue is public
CVE-2026-15719: Site isolation issue in the DOM: Navigation component.
Exploit code for this issue is public
CVE-2026-16349: Same-origin policy bypass in the DOM: Navigation component
CVE-2026-16350: Incorrect boundary conditions in the Audio/Video: cubeb
component
CVE-2026-16351: Sandbox escape due to use-after-free in the DOM: Navigation
component
CVE-2026-16352: Sandbox escape due to use-after-free in the Disability
Access APIs component
CVE-2026-16353: Invalid pointer in the DOM: Bindings (WebIDL) component
CVE-2026-16354: Information disclosure in the Graphics: ImageLib component
CVE-2026-16355: JIT miscompilation in the JavaScript Engine: JIT component
CVE-2026-16356: Sandbox escape due to use-after-free in the Disability
Access APIs component
CVE-2026-16357: Incorrect boundary conditions in the Graphics component
CVE-2026-16358: Site isolation issue in the Graphics: WebRender component
CVE-2026-16359: Incorrect boundary conditions in the Audio/Video: GMP
component
CVE-2026-16360: Memory safety bugs present in Thunderbird ESR 140.12 and
Thunderbird 152. Some of these bugs showed evidence of memory corruption
and we presume that with enough effort some of these could have been
exploited to run arbitrary code
CVE-2026-16361: Memory safety bugs present in Thunderbird ESR 140.12. Some
of these bugs showed evidence of memory corruption and we presume that with
enough effort some of these could have been exploited to run arbitrary code
CVE-2026-16362: Use-after-free in the WebRTC: Audio/Video component
CVE-2026-16363: JIT miscompilation in the JavaScript: WebAssembly component
CVE-2026-16368: Incorrect boundary conditions in the JavaScript:
WebAssembly component
CVE-2026-16369: Integer overflow in the JavaScript: WebAssembly component
CVE-2026-16371: Privilege escalation in the DOM: Navigation component
CVE-2026-16374: Information disclosure in the Framework component in
DevTools
CVE-2026-16375: Site isolation issue in the Networking: HTTP component
CVE-2026-16377: Mitigation bypass in the PDF Viewer component
CVE-2026-16379: Privilege escalation in the DOM: Content Processes
component
CVE-2026-16381: Same-origin policy bypass in the Networking: DNS component
CVE-2026-16383: Mitigation bypass in the DOM: Networking component
CVE-2026-16387: Site isolation issue in the Networking component
CVE-2026-16390: Mitigation bypass in the Enterprise Policies component
CVE-2026-16391: Information disclosure in the Storage: IndexedDB component
CVE-2026-16396: Privilege escalation in WebExtensions
CVE-2026-16405: Information disclosure in the Networking: WebSockets
component
CVE-2026-16412: Memory safety bugs present in Thunderbird ESR 140.12 and
Thunderbird 152. Some of these bugs showed evidence of memory corruption
and we presume that with enough effort some of these could have been
exploited to run arbitrary code
CVE-2026-57962: Memory exhaustion via a malicious LDAP address-book server
CVE-2026-57963: Content injection via HTML chat messages (Matrix/XMPP)