Mozilla developers and community members reported memory safety bugs present in Firefox 68. 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 < 69.

When a master password is set, it is required to be entered again before stored passwords can be accessed in the 'Saved Logins' dialog. It was found that locally stored passwords can be copied to the clipboard thorough the 'copy password' context menu item without re-entering the master password if the master password had been previously entered in the same session, allowing for potential theft of stored passwords. This vulnerability affects Firefox < 68.0.2 and Firefox ESR < 68.0.2.

A use-after-free vulnerability can occur in AssertWorkerThread due to a race condition with shared workers. This results in a potentially exploitable crash. This vulnerability affects Firefox < 67.

A use-after-free vulnerability can occur in the chrome event handler when it is freed while still in use. This results in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

A vulnerability where a JavaScript compartment mismatch can occur while working with the fetch API, resulting in a potentially exploitable crash. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

A race condition is present in the crash generation server used to generate data for the crash reporter. This issue can lead to a use-after-free in the main process, resulting in a potentially exploitable crash and a sandbox escape. *Note: this vulnerability only affects Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Images from a different domain can be read using a canvas object in some circumstances. This could be used to steal image data from a different site in violation of same-origin policy. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

A possible vulnerability exists where type confusion can occur when manipulating JavaScript objects in object groups, allowing for the bypassing of security checks within these groups. *Note: this vulnerability has only been demonstrated with UnboxedObjects, which are disabled by default on all supported releases.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

If hyperthreading is not disabled, a timing attack vulnerability exists, similar to previous Spectre attacks. Apple has shipped macOS 10.14.5 with an option to disable hyperthreading in applications running untrusted code in a thread through a new sysctl. Firefox now makes use of it on the main thread and any worker threads. *Note: users need to update to macOS 10.14.5 in order to take advantage of this change.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.

Mozilla developers and community members reported memory safety bugs present in Firefox 66. 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 < 67.

As part of a winning Pwn2Own entry, a researcher demonstrated a sandbox escape by installing a malicious language pack and then opening a browser feature that used the compromised translation. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

Mozilla developers and community members reported memory safety bugs present in Firefox 66, Firefox ESR 60.6, and Thunderbird 60.6. 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 < 60.7, Firefox < 67, and Firefox ESR < 60.7.

A vulnerability exists where if a user opens a locally saved HTML file, this file can use file: URIs to access other files in the same directory or sub-directories if the names are known or guessed. The Fetch API can then be used to read the contents of any files stored in these directories and they may uploaded to a server. It was demonstrated that in combination with a popular Android messaging app, if a malicious HTML attachment is sent to a user and they opened that attachment in Firefox, due to that app's predictable pattern for locally-saved file names, it is possible to read attachments the victim received from other correspondents. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

Empty or malformed p256-ECDH public keys may trigger a segmentation fault due values being improperly sanitized before being copied into memory and used. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.

The HTTP Alternative Services header, Alt-Svc, can be used by a malicious site to scan all TCP ports of any host that the accessible to a user when web content is loaded. This vulnerability affects Firefox < 68.

A vulnerability exists where it possible to force Network Security Services (NSS) to sign CertificateVerify with PKCS#1 v1.5 signatures when those are the only ones advertised by server in CertificateRequest in TLS 1.3. PKCS#1 v1.5 signatures should not be used for TLS 1.3 messages. This vulnerability affects Firefox < 68.

When a user navigates to site marked as unsafe by the Safebrowsing API, warning messages are displayed and navigation is interrupted but resources from the same site loaded through websockets are not blocked, leading to the loading of unsafe resources and bypassing safebrowsing protections. This vulnerability affects Firefox < 68.

Application permissions give additional remote troubleshooting permission to the site input.mozilla.org, which has been retired and now redirects to another site. This additional permission is unnecessary and is a potential vector for malicious attacks. This vulnerability affects Firefox < 68.

A vulnerability exists during the installation of add-ons where the initial fetch ignored the origin attributes of the browsing context. This could leak cookies in private browsing mode or across different "containers" for people who use the Firefox Multi-Account Containers Web Extension. This vulnerability affects Firefox < 68.

The unicode latin 'kra' character can be used to spoof a standard 'k' character in the addressbar. This allows for domain spoofing attacks as do not display as punycode text, allowing for user confusion. This vulnerability affects Firefox < 68.