An iframe that was not permitted to run scripts could do so if the user clicked on a <code>javascript:</code> link. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.

Mozilla developers Andrew McCreight, Nicolas B. Pierron, and the Mozilla Fuzzing Team reported memory safety bugs present in Firefox 100 and Firefox ESR 91.9. 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 Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

An attacker could have injected CSS into stylesheets accessible via internal URIs, such as resource:, and in doing so bypass a page's Content Security Policy. This vulnerability affects Firefox ESR < 91.11, Thunderbird < 102, Thunderbird < 91.11, and Firefox < 101.

An attacker could have exploited a timing attack by sending a large number of allowCredential entries and detecting the difference between invalid key handles and cross-origin key handles. This could have led to cross-origin account linking in violation of WebAuthn goals. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

A crafted CMS message could have been processed incorrectly, leading to an invalid memory read, and potentially further memory corruption. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

On arm64, WASM code could have resulted in incorrect assembly generation leading to a register allocation problem, and a potentially exploitable crash. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

When downloading files on Windows, the % character was not escaped, which could have lead to a download incorrectly being saved to attacker-influenced paths that used variables such as %HOMEPATH% or %APPDATA%.<br>*This bug only affects Firefox for Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

When exiting fullscreen mode, an iframe could have confused the browser about the current state of fullscreen, resulting in potential user confusion or spoofing attacks. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

A malicious webpage could have caused an out-of-bounds write in WebGL, leading to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

A malicious website could have learned the size of a cross-origin resource that supported Range requests. This vulnerability affects Thunderbird < 91.10, Firefox < 101, and Firefox ESR < 91.10.

Mozilla developers and the Mozilla Fuzzing Team reported memory safety bugs present in Firefox 102. 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 ESR < 102.1, Firefox < 103, and Thunderbird < 102.1.

An OpenPGP digital signature includes information about the date when the signature was created. When displaying an email that contains a digital signature, the email's date will be shown. If the dates were different, then Thunderbird didn't report the email as having an invalid signature. If an attacker performed a replay attack, in which an old email with old contents are resent at a later time, it could lead the victim to believe that the statements in the email are current. Fixed versions of Thunderbird will require that the signature's date roughly matches the displayed date of the email. This vulnerability affects Thunderbird < 102 and Thunderbird < 91.11.

If an object prototype was corrupted by an attacker, they would have been able to set undesired attributes on a JavaScript object, leading to privileged code execution. This vulnerability affects Firefox < 102, Firefox ESR < 91.11, Thunderbird < 102, and Thunderbird < 91.11.

When displaying the sender of an email, and the sender name contained the Braille Pattern Blank space character multiple times, Thunderbird would have displayed all the spaces. This could have been used by an attacker to send an email message with the attacker's digital signature, that was shown with an arbitrary sender email address chosen by the attacker. If the sender name started with a false email address, followed by many Braille space characters, the attacker's email address was not visible. Because Thunderbird compared the invisible sender address with the signature's email address, if the signing key or certificate was accepted by Thunderbird, the email was shown as having a valid digital signature. This vulnerability affects Thunderbird < 91.10.

The ElGamal implementation in Botan through 2.18.1, as used in Thunderbird and other products, allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.

Mozilla Necko, as used in Firefox, SeaMonkey, and other applications, performs DNS prefetching of domain names contained in links within local HTML documents, which makes it easier for remote attackers to determine the network location of the application's user by logging DNS requests. NOTE: the vendor disputes the significance of this issue, stating "I don't think we necessarily need to worry about that case."

Mozilla Firefox before 3.0.16 and 3.5.x before 3.5.6, and SeaMonkey before 2.0.1, allows remote attackers to spoof an SSL indicator for an http URL or a file URL by setting document.location to an https URL corresponding to a site that responds with a No Content (aka 204) status code and an empty body.

Mozilla Firefox before 3.0.16 and 3.5.x before 3.5.6, and SeaMonkey before 2.0.1, allows remote attackers to send authenticated requests to arbitrary applications by replaying the NTLM credentials of a browser user.

Multiple unspecified vulnerabilities in the JavaScript engine in Mozilla Firefox 3.5.x before 3.5.6, SeaMonkey before 2.0.1, and Thunderbird allow remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.

Unspecified vulnerability in the browser engine in Mozilla Firefox before 3.0.16, SeaMonkey before 2.0.1, and Thunderbird allows remote attackers to cause a denial of service (memory corruption and application crash) or possibly execute arbitrary code via unknown vectors.