Accessibility. A privacy issue was addressed by removing sensitive data.

Same-origin policy bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Incorrect boundary conditions in the Audio/Video: Web Codecs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Sandbox escape due to incorrect boundary conditions in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Spoofing issue in WebExtensions. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Use-after-free in the DOM: Bindings (WebIDL) component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Incorrect boundary conditions, integer overflow in the Audio/Video component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Sandbox escape due to use-after-free in the Disability Access APIs component. This vulnerability was fixed in Firefox 151, Firefox ESR 115.36, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Privilege escalation in the DOM: Workers component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Same-origin policy bypass in the DOM: Networking component. This vulnerability was fixed in Firefox 151 and Thunderbird 151.

Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Integer overflow in the Networking: JAR component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Integer overflow in the Widget: Win32 component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.

Privilege escalation in the Panning and Zooming component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158 and Thunderbird 158.

Privilege escalation in the Application Update component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

In libexpat before 2.2.8, crafted XML input could fool the parser into changing from DTD parsing to document parsing too early; a consecutive call to XMLGetCurrentLineNumber (or XMLGetCurrentColumnNumber) then resulted in a heap-based buffer over-read.

Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Information disclosure, privilege escalation in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.

Use-after-free in the Widget component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Uninitialized memory in the Storage: Quota Manager component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 140.17, Thunderbird 153.4, Firefox 157, Firefox ESR 115.42, and Firefox ESR 140.17.

Sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox ESR 153.4, Thunderbird 157, Thunderbird 153.4, and Firefox 157.

Privilege escalation due to use-after-free in the Graphics: WebGPU component. This vulnerability was fixed in Thunderbird 157 and Firefox 157.

A malicious, compromised, or MITM-controlled Exchange server can return a single well-formed SOAP response containing an element with enough attributes to keep Thunderbird's main thread CPU-bound for seconds to hours.

Several buffer-growth sites in libmime performed size arithmetic in 32-bit types without overflow checks. On a sufficiently large message the growth guard could fail open, or the buffer could be reallocated smaller than required, and a subsequent memcpy would then write attacker-controlled data across adjacent heap allocations.

Mitigation bypass in the File Handling component. This vulnerability was fixed in Firefox ESR 153.5 and Thunderbird 153.5.