Mozilla vulnerabilities
We track 912 vulnerabilities in Mozilla products across 22 products. 911 are rated high or critical, and 15 have been exploited in real attacks. The most recent was published on November 10, 2026.
Latest Mozilla vulnerabilities
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 9.8 Critical severity
Firefox: Access of Uninitialized Pointer
Invalid pointer in the Graphics: WebRender component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the Layout: Block and Inline component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.1 High severity
Firefox: Origin Validation Error
Same-origin policy bypass in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Access of Uninitialized Pointer
Invalid pointer in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Editor component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the Networking: HTTP component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the Layout: Tables component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Use After Free
Privilege escalation due to use-after-free in the WebRTC: Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Use After Free
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Access of Resource Using Incompatible Type
JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.1 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the Graphics: Text component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: HTML Parser component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the Layout: Tables component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.1 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the Audio/Video: Playback component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the JavaScript: Standard Library component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Use After Free
Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.8 High severity
Firefox: Use After Free
Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 9.6 Critical severity
Firefox: Protection Mechanism Failure
Sandbox escape in the DOM: Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Use After Free
Use-after-free in the Layout component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 7.3 High severity
Firefox: Use After Free
Privilege escalation due to use-after-free in the Graphics: Canvas2D component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 9.8 Critical severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Privilege escalation due to incorrect boundary conditions in the Networking component. This vulnerability was fixed in Firefox 159, Firefox ESR 115.44, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 9.6 Critical severity
Firefox: Protection Mechanism Failure
Sandbox escape in the DOM: Navigation component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 8.1 High severity
Firefox: Origin Validation Error
Same-origin policy bypass in the DOM: Navigation component. This vulnerability was fixed in Firefox 159, Firefox ESR 153.6, Thunderbird 159, and Thunderbird 153.6.
- 9.1 Critical severity
Thunderbird: Improper Encoding or Escaping of Output
Thunderbird did not escape attribute values when serializing outgoing XMPP stanzas. Because values from incoming requests were echoed back in automatic replies, a remote XMPP user could send a crafted request that caused Thunderbird to inject arbitrary stanzas
- 8.6 High severity
Thunderbird: Uncontrolled Resource Consumption
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. This vulnerability was fixed in Thunderbir
- 8.4 High severity
Thunderbird: Integer Overflow or Wraparound
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
- 8.8 High severity
Firefox: Improper Privilege Management
Privilege escalation in the WebExtensions component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
- 8.1 High severity
Firefox: Protection Mechanism Failure
Mitigation bypass in the Enterprise Policies component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
- 8.8 High severity
Firefox: Improper Restriction of Operations within the Bounds of a Memory Buffer
Incorrect boundary conditions in the SVG component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
- 8.1 High severity
Firefox: Protection Mechanism Failure
Mitigation bypass in the Networking: HTTP component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
- 8.1 High severity
Firefox: Origin Validation Error
Site isolation issue in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
- 8.3 High severity
Firefox: Concurrent Execution using Shared Resource with Improper Synchronization
Sandbox escape due to race condition in the Networking component. This vulnerability was fixed in Firefox 158, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.