The cache directory on the local file system is set to be world writable. Firefox defaults to extracting libraries from this cache. This allows for the possibility of an installed malicious application or tools with write access to the file system to replace files used by Firefox with their own versions. This vulnerability affects Firefox < 51.0.3.

Memory safety bugs were reported in Thunderbird 45.7. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Memory safety bugs were reported in Firefox 51. Some of these bugs showed evidence of memory corruption and we presume that with enough effort that some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 52 and Thunderbird < 52.

JIT-spray targeting asm.js combined with a heap spray allows for a bypass of ASLR and DEP protections leading to potential memory corruption attacks. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

A crash triggerable by web content in which an "ErrorResult" references unassigned memory due to a logic error. The resulting crash may be exploitable. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

A use-after-free can occur when events are fired for a "FontFace" object after the object has been already been destroyed while working with fonts. This results in a potentially exploitable crash. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

When adding a range to an object in the DOM, it is possible to use "addRange" to add the range to an incorrect root object. This triggers a use-after-free, resulting in a potentially exploitable crash. This vulnerability affects Firefox < 52 and Thunderbird < 52.

A use-after-free error can occur when manipulating ranges in selections with one node inside a native anonymous tree and one node outside of it. This results in a potentially exploitable crash. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Certain response codes in FTP connections can result in the use of uninitialized values for ports in FTP operations. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

A segmentation fault can occur in the Skia graphics library during some canvas operations due to issues with mask/clip intersection and empty masks. This vulnerability affects Firefox < 52 and Thunderbird < 52.

Using SVG filters that don't use the fixed point math implementation on a target iframe, a malicious page can extract pixel values from a targeted user. This can be used to extract history information and read text values across domains. This violates same-origin policy and leads to information disclosure. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

Video files loaded video captions cross-origin without checking for the presence of CORS headers permitting such cross-origin use, leading to potential information disclosure for video captions. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

The Mozilla Windows updater can be called by a non-privileged user to delete an arbitrary local file by passing a special path to the callback parameter through the Mozilla Maintenance Service, which has privileged access. Note: This attack requires local system access and only affects Windows. Other operating systems are not affected. This vulnerability affects Firefox ESR < 45.8 and Firefox < 52.

Memory corruption resulting in a potentially exploitable crash during garbage collection of JavaScript due errors in how incremental sweeping is managed for memory cleanup. This vulnerability affects Firefox < 52, Firefox ESR < 45.8, Thunderbird < 52, and Thunderbird < 45.8.

A use-after-free can occur during buffer storage operations within the ANGLE graphics library, used for WebGL content. The buffer storage can be freed while still in use in some circumstances, leading to a potentially exploitable crash. Note: This issue is in "libGLES", which is only in use on Windows. Other operating systems are not affected. This vulnerability affects Firefox < 52 and Thunderbird < 52.

A buffer overflow read during SVG filter color value operations, resulting in data exposure. This vulnerability affects Firefox < 52 and Thunderbird < 52.

A segmentation fault can occur during some bidirectional layout operations. This vulnerability affects Firefox < 52 and Thunderbird < 52.

The file picker dialog can choose and display the wrong local default directory when instantiated. On some operating systems, this can lead to information disclosure, such as the operating system or the local account name. This vulnerability affects Firefox < 52 and Thunderbird < 52.

An attack can use a blob URL and script to spoof an arbitrary addressbar URL prefaced by "blob:" as the protocol, leading to user confusion and further spoofing attacks. This vulnerability affects Firefox < 52.

In certain circumstances a networking event listener can be prematurely released. This appears to result in a null dereference in practice. This vulnerability affects Firefox < 52 and Thunderbird < 52.

When dragging content from the primary browser pane to the addressbar on a malicious site, it is possible to change the addressbar so that the displayed location following navigation does not match the URL of the newly loaded page. This allows for spoofing attacks. This vulnerability affects Firefox < 52.

An out of bounds read error occurs when parsing some HTTP digest authorization responses, resulting in information leakage through the reading of random memory containing matches to specifically set patterns. This vulnerability affects Firefox < 52 and Thunderbird < 52.

If a malicious site repeatedly triggers a modal authentication prompt, eventually the browser UI will become non-responsive, requiring shutdown through the operating system. This is a denial of service (DOS) attack. This vulnerability affects Firefox < 52 and Thunderbird < 52.

A "javascript:" url loaded by a malicious page can obfuscate its location by blanking the URL displayed in the addressbar, allowing for an attacker to spoof an existing page without the malicious page's address being displayed correctly. This vulnerability affects Firefox < 52.

A malicious site could spoof the contents of the print preview window if popup windows are enabled, resulting in user confusion of what site is currently loaded. This vulnerability affects Firefox < 52 and Thunderbird < 52.

If a malicious site uses the "view-source:" protocol in a series within a single hyperlink, it can trigger a non-exploitable browser crash when the hyperlink is selected. This was fixed by no longer making "view-source:" linkable. This vulnerability affects Firefox < 52 and Thunderbird < 52.

The Gecko Media Plugin sandbox allows access to local files that match specific regular expressions. On OS OX, this matching allows access to some data in subdirectories of "/private/var" that could expose personal or temporary data. This has been updated to not allow access to "/private/var" and its subdirectories. Note: this issue only affects OS X. Other operating systems are not affected. This vulnerability affects Firefox < 52 and Thunderbird < 52.

On Linux, if the secure computing mode BPF (seccomp-bpf) filter is running when the Gecko Media Plugin sandbox is started, the sandbox fails to be applied and items that would run within the sandbox are run protected only by the running filter which is typically weak compared to the sandbox. Note: this issue only affects Linux. Other operating systems are not affected. This vulnerability affects Firefox < 52 and Thunderbird < 52.

A non-existent chrome.manifest file will attempt to be loaded during startup from the primary installation directory. If a malicious user with local access puts chrome.manifest and other referenced files in this directory, they will be loaded and activated during startup. This could result in malicious software being added without consent or modification of referenced installed files. This vulnerability affects Firefox < 52.