Memory safety bugs were reported in Firefox 52, Firefox ESR 45.8, Firefox ESR 52, and Thunderbird 52. 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 Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

An integer overflow in "createImageBitmap()" was reported through the Pwn2Own contest. The fix for this vulnerability disables the experimental extensions to the "createImageBitmap" API. This function runs in the content sandbox, requiring a second vulnerability to compromise a user's computer. This vulnerability affects Firefox ESR < 52.0.1 and Firefox < 52.0.1.

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.

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.

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.

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.

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 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.

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.

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.