The Mozilla Maintenance Service does not guard against files being hardlinked to another file in the updates directory, allowing for the replacement of local files, including the Maintenance Service executable, which is run with privileged access. Additionally, there was a race condition during checks for junctions and symbolic links by the Maintenance Service, allowing for potential local file and directory manipulation to be undetected in some circumstances. This allows for potential privilege escalation by a user with unprivileged local access.
*Note: These attacks requires local system access and only affects Windows. Other operating systems are not affected.*. This vulnerability affects Firefox < 69 and Firefox ESR < 68.1.
firefox
CVE-2019-11721
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.
CVE-2019-11720
Some unicode characters are incorrectly treated as whitespace during the parsing of web content instead of triggering parsing errors. This allows malicious code to then be processed, evading cross-site scripting (XSS) filtering. This vulnerability affects Firefox < 68.
CVE-2019-11702
A hyperlink using protocols associated with Internet Explorer, such as IE.HTTP:, can be used to open local files at a known location with Internet Explorer if a user approves execution when prompted. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 67.0.2.
CVE-2019-11700
A hyperlink using the res: protocol can be used to open local files at a known location in Internet Explorer if a user approves execution when prompted. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Firefox < 67.
CVE-2019-11694
A vulnerability exists in the Windows sandbox where an uninitialized value in memory can be leaked to a renderer from a broker when making a call to access an otherwise unavailable file. This results in the potential leaking of information stored at that memory location. *Note: this issue only occurs on Windows. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.7, Firefox < 67, and Firefox ESR < 60.7.