Mozilla developers reported memory safety bugs present in Firefox 70. 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 < 71.

Mozilla developers reported memory safety bugs present in Firefox 70 and Firefox ESR 68.2. 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 Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

Under certain conditions, when retrieving a document from a DocShell in the antitracking code, a race condition could cause a use-after-free condition and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

Under certain conditions, when checking the Resist Fingerprinting preference during device orientation checks, a race condition could have caused a use-after-free and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

When running, the updater service wrote status and log files to an unrestricted location; potentially allowing an unprivileged process to locate and exploit a vulnerability in file handling in the updater service. *Note: This attack requires local system access and only affects Windows. Other operating systems are not affected.*. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

When using nested workers, a use-after-free could occur during worker destruction. This resulted in a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

The plain text serializer used a fixed-size array for the number of <ol> elements it could process; however it was possible to overflow the static-sized array leading to memory corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.

If upgrade-insecure-requests was specified in the Content Security Policy, and a link was dragged and dropped from that page, the link was not upgraded to https. This vulnerability affects Firefox < 70.

An object tag with a data URI did not correctly inherit the document's Content Security Policy. This allowed a CSP bypass in a cross-origin frame if the document's policy explicitly allowed data: URIs. This vulnerability affects Firefox < 70.

A compromised content process could send a message to the parent process that would cause the 'Click to Play' permission prompt to be shown. However, due to lack of validation from the parent process, if the user accepted the permission request an attacker-controlled permission would be granted rather than the 'Click to Play' permission. This vulnerability affects Firefox < 70.

Mozilla developers and community members reported memory safety bugs present in Firefox 69 and Firefox ESR 68.1. Some of these bugs showed evidence of memory corruption and we presume that with enough effort some of these could be exploited to run arbitrary code. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

Failure to correctly handle null bytes when processing HTML entities resulted in Firefox incorrectly parsing these entities. This could have led to HTML comment text being treated as HTML which could have led to XSS in a web application under certain conditions. It could have also led to HTML entities being masked from filters - enabling the use of entities to mask the actual characters of interest from filters. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

If two same-origin documents set document.domain differently to become cross-origin, it was possible for them to call arbitrary DOM methods/getters/setters on the now-cross-origin window. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

By using a form with a data URI it was possible to gain access to the privileged JSONView object that had been cloned into content. Impact from exposing this object appears to be minimal, however it was a bypass of existing defense in depth mechanisms. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

A fixed-size stack buffer could overflow in nrappkit when doing WebRTC signaling. This resulted in a potentially exploitable crash in some instances. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

An attacker could have caused 4 bytes of HMAC output to be written past the end of a buffer stored on the stack. This could be used by an attacker to execute arbitrary code or more likely lead to a crash. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

Mozilla community member Philipp reported a memory safety bug present in Firefox 68 when 360 Total Security was installed. This bug showed evidence of memory corruption in the accessibility engine and we presume that with enough effort that it could be exploited to run arbitrary code. This vulnerability affects Firefox < 69, Thunderbird < 68.2, and Firefox ESR < 68.2.

When following the value's prototype chain, it was possible to retain a reference to a locale, delete it, and subsequently reference it. This resulted in a use-after-free and a potentially exploitable crash. This vulnerability affects Firefox < 70, Thunderbird < 68.2, and Firefox ESR < 68.2.

Improper refcounting of soft token session objects could cause a use-after-free and crash (likely limited to a denial of service). This vulnerability affects Firefox < 71.

When encrypting with a block cipher, if a call to NSC_EncryptUpdate was made with data smaller than the block size, a small out of bounds write could occur. This could have caused heap corruption and a potentially exploitable crash. This vulnerability affects Thunderbird < 68.3, Firefox ESR < 68.3, and Firefox < 71.