Mozilla developers and community members Andreea Pavel, Christian Holler, Honza Bambas, Jason Kratzer, and Jeff Gilbert reported memory safety bugs present in Firefox 67 and Firefox ESR 60.7. 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.
Mozilla developers and community members André Bargull, Christian Holler, Natalia Csoregi, Raul Gurzau, Daniel Varga, Jon Coppeard, Marcia Knous, Gary Kwong, Randell Jesup, David Bolter, Jeff Gilbert, and Deian Stefan reported memory safety bugs present in Firefox 67. 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.
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.
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.
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.
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.
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.
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. Luigi Gubello 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.