A use-after-free vulnerability can occur when deleting an input element during a mutation event handler triggered by focusing that element. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Memory safety bugs present in Firefox 60, Firefox ESR 60, and Firefox ESR 52.8. 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 < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Memory safety bugs present in Firefox 60. 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 < 61.

A compromised IPC child process can escape the content sandbox and list the names of arbitrary files on the file system without user consent or interaction. This could result in exposure of private local files. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

An integer overflow can occur in the SwizzleData code while calculating buffer sizes. The overflowed value is used for subsequent graphics computations when their inputs are not sanitized which results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, and Firefox < 61.

A vulnerability can occur when capturing a media stream when the media source type is changed as the capture is occurring. This can result in stream data being cast to the wrong type causing a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

Plaintext of decrypted emails can leak through by user submitting an embedded form by pressing enter key within a text input field. This vulnerability affects Thunderbird < 52.9.

A buffer overflow can occur when rendering canvas content while adjusting the height and width of the canvas element dynamically, causing data to be written outside of the currently computed boundaries. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60, Thunderbird < 52.9, Firefox ESR < 60.1, Firefox ESR < 52.9, and Firefox < 61.

dDecrypted S/MIME parts hidden with CSS or the plaintext HTML tag can leak plaintext when included in a HTML reply/forward. This vulnerability affects Thunderbird < 52.9.

In the previous mitigations for Spectre, the resolution or precision of various methods was reduced to counteract the ability to measure precise time intervals. In that work PerformanceNavigationTiming was not adjusted but it was found that it could be used as a precision timer. This vulnerability affects Thunderbird < 60, Firefox ESR < 60.1, and Firefox < 61.