Security Vulnerabilities fixed in Firefox 123 — Mozilla

When storing and re-accessing data on a networking channel, the length of buffers may have been confused, resulting in an out-of-bounds memory read.
Through a series of API calls and redirects, an attacker-controlled alert dialog could have been displayed on another website (with the victim website’s URL shown).
The fetch() API and navigation incorrectly shared the same cache, as the cache key did not include the optional headers fetch() may contain. Under the correct circumstances, an attacker may have been able to poison the local browser cache by priming it with a fetch() response controlled by the additional headers. Upon navigation to the same URL, the user would see the cached response instead of the expected response.
A website could have obscured the fullscreen notification by using a dropdown select input element. This could have led to user confusion and possible spoofing attacks.
If a website set a large custom cursor, portions of the cursor could have overlapped with the permission dialog, potentially resulting in user confusion and unexpected granted permissions.
A malicious website could have used a combination of exiting fullscreen mode and requestPointerLock to cause the user’s mouse to be re-positioned unexpectedly, which could have led to user confusion and inadvertently granting permissions they did not intend to grant.
Set-Cookie response headers were being incorrectly honored in multipart HTTP responses. If an attacker could control the Content-Type response header, as well as control part of the response body, they could inject Set-Cookie response headers that would have been honored by the browser.
When opening a website using the firefox:// protocol handler, SameSite cookies were not properly respected.
The incorrect object was checked for NULL in the built-in profiler, potentially leading to invalid memory access and undefined behavior. Note: This issue only affects the application when the profiler is running.
Incorrect code generation could have led to unexpected numeric conversions and potential undefined behavior. Note: This issue only affects 32-bit ARM devices.
Memory safety bugs present in Firefox 122, Firefox ESR 115.7, and Thunderbird 115.7. 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.
Memory safety bugs present in Firefox 122. 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.