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.

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.

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.

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 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.

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 128.5, and Thunderbird 128.5. 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, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.

Memory safety bugs present in Firefox 133, Thunderbird 133, Firefox ESR 115.18, Firefox ESR 128.5, Thunderbird 115.18, and Thunderbird 128.5. 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, Firefox ESR < 128.6, Firefox ESR < 115.19, Thunderbird < 134, and Thunderbird < 128.6.

When segmenting specially crafted text, segmentation would corrupt memory leading to a potentially exploitable crash. This vulnerability affects Firefox < 134, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.

Parsing a JavaScript module as JSON could, under some circumstances, cause cross-compartment access, which may result in a use-after-free. This vulnerability affects Firefox < 134, Firefox ESR < 128.6, Thunderbird < 134, and Thunderbird < 128.6.

When using Alt-Svc, ALPN did not properly validate certificates when the original server is redirecting to an insecure site. 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.

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.

Missing thread synchronization primitives could have led to a data race on members of the PlaybackParams structure. This vulnerability affects Firefox < 133 and Thunderbird < 133.

A null pointer dereference may have inadvertently occurred in `pk12util`, and specifically in the `SEC_ASN1DecodeItem_Util` function, when handling malformed or improperly formatted input files. This vulnerability affects Firefox < 133 and Thunderbird < 133.

`NSC_DeriveKey` inadvertently assumed that the `phKey` parameter is always non-NULL. When it was passed as NULL, a segmentation fault (SEGV) occurred, leading to crashes. This behavior conflicted with the PKCS#11 v3.0 specification, which allows `phKey` to be NULL for certain mechanisms. This vulnerability affects Firefox < 133 and Thunderbird < 133.

A double-free issue could have occurred in `sec_pkcs7_decoder_start_decrypt()` when handling an error path. Under specific conditions, the same symmetric key could have been freed twice, potentially leading to memory corruption. This vulnerability affects Firefox < 133, Thunderbird < 133, Firefox ESR < 128.7, and Thunderbird < 128.7.

On Android, Firefox may have inadvertently allowed viewing saved passwords without the required device PIN authentication. This vulnerability affects Firefox < 133.

Copying sensitive information from Private Browsing tabs on Android, such as passwords, may have inadvertently stored data in the cloud-based clipboard history if enabled. This vulnerability affects Firefox < 133 and Thunderbird < 133.

The incorrect domain may have been displayed in the address bar during an interrupted navigation attempt. This could have led to user confusion and possible spoofing attacks. This vulnerability affects Firefox < 133 and Thunderbird < 133.

Malicious websites may have been able to perform user intent confirmation through tapjacking. This could have led to users unknowingly approving the launch of external applications, potentially exposing them to underlying vulnerabilities. This vulnerability affects Firefox < 133 and Thunderbird < 133.