Memory safety bugs present in Firefox 134, Thunderbird 134, Firefox ESR 128.6, and Thunderbird 128.6. 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. This vulnerability affects Firefox < 135, Firefox ESR < 128.7, Thunderbird < 128.7, and Thunderbird < 135.
An attacker could have caused a use-after-free via crafted XSLT data, leading to a potentially exploitable crash. This vulnerability affects Firefox < 135, Firefox ESR < 115.20, Firefox ESR < 128.7, Thunderbird < 128.7, and Thunderbird < 135.
An attacker could have caused a use-after-free via the Custom Highlight API, leading to a potentially exploitable crash. This vulnerability affects Firefox < 135, Firefox ESR < 115.20, Firefox ESR < 128.7, Thunderbird < 128.7, and Thunderbird < 135.
A bug in WebAssembly code generation could have lead to a crash. It may have been possible for an attacker to leverage this to achieve code execution. This vulnerability affects Firefox < 135, Firefox ESR < 128.7, Thunderbird < 128.7, and Thunderbird < 135.
When redirecting to an invalid protocol scheme, an attacker could spoof the address bar.
*Note: This issue only affected Android operating systems. Other operating systems are unaffected.* This vulnerability affects Firefox < 134.
Under certain circumstances, a user opt-in setting that Focus should require authentication before use could have been be bypassed. This vulnerability affects Firefox < 134.
When using an invalid protocol scheme, an attacker could spoof the address bar.
*Note: This issue only affected Android operating systems. Other operating systems are unaffected.*
*Note: This issue is a different issue from CVE-2025-0244. This vulnerability affects Firefox < 134.
Memory safety bugs present in Firefox 133 and Thunderbird 133. 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. This vulnerability affects Firefox < 134 and Thunderbird < 134.
The WebChannel API, which is used to transport various information across processes, did not check the sending principal but rather accepted the principal being sent. This could have led to privilege escalation attacks. This vulnerability affects Firefox < 134, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.
Assuming a controlled failed memory allocation, an attacker could have caused a use-after-free, leading to a potentially exploitable crash. This vulnerability affects Firefox < 134, Firefox ESR < 128.6, Firefox ESR < 115.19, Thunderbird < 134, and Thunderbird < 128.6.