When an https: web page created a pop-up from a "javascript:" URL, that pop-up was incorrectly allowed to load blockable content such as iframes from insecure http: URLs This vulnerability affects Firefox < 120.

Mozilla: Incorrect parsing of relative URLs starting with "///"

Relative URLs starting with three slashes were incorrectly parsed, and a path-traversal "/../" part in the path could be used to override the specified host. This could contribute to security problems in web sites. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Mozilla: Using Selection API would copy contents into X11 primary selection.

When using X11, text selected by the page using the Selection API was erroneously copied into the primary selection, a temporary storage not unlike the clipboard. *This bug only affects Firefox on X11. Other systems are unaffected.* This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Mozilla: Use-after-free in ReadableByteStreamQueueEntry::Buffer

Ownership mismanagement led to a use-after-free in ReadableByteStreams This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Mozilla: Clickjacking permission prompts using the fullscreen transition

The black fade animation when exiting fullscreen is roughly the length of the anti-clickjacking delay on permission prompts. It was possible to use this fact to surprise users by luring them to click where the permission grant button would be about to appear. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Mozilla: Use-after-free in MessagePort::Entangled

It was possible to cause the use of a MessagePort after it had already been freed, which could potentially have led to an exploitable crash. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

Mozilla: Out-of-bound memory access in WebGL2 blitFramebuffer

On some systems—depending on the graphics settings and drivers—it was possible to force an out-of-bounds read and leak memory data into the images created on the canvas element. This vulnerability affects Firefox < 120, Firefox ESR < 115.5.0, and Thunderbird < 115.5.

nss: vulnerable to Minerva side-channel information leak

Multiple NSS NIST curves were susceptible to a side-channel attack known as "Minerva". This attack could potentially allow an attacker to recover the private key. This vulnerability affects Firefox < 121.

Memory safety bugs present in Firefox 118. 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 < 119.

Mozilla: Memory safety bugs fixed in Firefox 119, Firefox ESR 115.4, and Thunderbird 115.4

Memory safety bugs present in Firefox 118, Firefox ESR 115.3, and Thunderbird 115.3. 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 < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

A malicious web site can enter fullscreen mode while simultaneously triggering a WebAuthn prompt. This could have obscured the fullscreen notification and could have been leveraged in a spoofing attack. This vulnerability affects Firefox < 119.

Mozilla: Improper object tracking during GC in the JavaScript engine could have led to a crash.

During garbage collection extra operations were performed on a object that should not be. This could have led to a potentially exploitable crash. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

Mozilla: WebExtensions could open arbitrary URLs

A malicious installed WebExtension could open arbitrary URLs, which under the right circumstance could be leveraged to collect sensitive user data. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

Mozilla: Large WebGL draw could have led to a crash

Drivers are not always robust to extremely large draw calls and in some cases this scenario could have led to a crash. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

An attacker with temporary script access to a site could have set a cookie containing invalid characters using `document.cookie` that could have led to unknown errors. This vulnerability affects Firefox < 119.

Using iterative requests an attacker was able to learn the size of an opaque response, as well as the contents of a server-supplied Vary header. This vulnerability affects Firefox < 119.

Mozilla: Queued up rendering could have allowed websites to clickjack

It was possible for certain browser prompts and dialogs to be activated or dismissed unintentionally by the user due to an insufficient activation-delay. This vulnerability affects Firefox < 119, Firefox ESR < 115.4, and Thunderbird < 115.4.1.

In a non-standard configuration of Firefox, an integer overflow could have occurred based on network traffic (possibly under influence of a local unprivileged webpage), leading to an out-of-bounds write to privileged process memory. *This bug only affects Firefox if a non-standard preference allowing non-HTTPS Alternate Services (`network.http.altsvc.oe`) is enabled.* This vulnerability affects Firefox < 118.

Mozilla: Use-after-free in Ion Compiler

During Ion compilation, a Garbage Collection could have resulted in a use-after-free condition, allowing an attacker to write two NUL bytes, and cause a potentially exploitable crash. This vulnerability affects Firefox < 118, Firefox ESR < 115.3, and Thunderbird < 115.3.

In canvas rendering, a compromised content process could have caused a surface to change unexpectedly, leading to a memory leak of a privileged process. This memory leak could be used to effect a sandbox escape if the correct data was leaked. This vulnerability affects Firefox < 118.