The WebGL `DrawElementsInstanced` method was susceptible to a heap buffer overflow when used on systems with the Mesa VM driver. This issue could allow an attacker to perform remote code execution and sandbox escape. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. When resolving a symlink, a race may occur where the buffer passed to `readlink` may actually be smaller than necessary. *This bug only affects Firefox on Unix-based operating systems . Windows is unaffected.* This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. Firefox was susceptible to a heap buffer overflow in `nsTextFragment` due to insufficient OOM handling. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. A use-after-free condition affected TLS socket creation when under memory pressure. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. The `VideoBridge` allowed any content process to use textures produced by remote decoders. This could be abused to escape the sandbox. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. The `nsWindow::PickerOpen` method was susceptible to a heap buffer overflow when running in headless mode. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. A use-after-free was identified in the `nsDNSService::Init`. This issue appears to manifest rarely during start-up. This vulnerability affects Firefox ESR less than 115.6 and Thunderbird less than 115.6. The `ShutdownObserver` was susceptible to potentially undefined behavior due to its reliance on a dynamic type that lacked a virtual destructor. This vulnerability affects Firefox ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. Memory safety bugs present in Firefox 120, Firefox ESR 115.5, and Thunderbird 115.5. 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 ESR less than 115.6, Thunderbird less than 115.6, and Firefox less than 121. `EncryptingOutputStream` was susceptible to exposing uninitialized data. This issue could only be abused in order to write data to a local disk which may have implications for private browsing mode. This vulnerability affects Firefox ESR less than 115.6 and Firefox less than 121. The timing of a button click causing a popup to disappear was approximately the same length as 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 ESR less than 115.6 and Firefox less than 121