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.
thunderbird
CVE-2019-9811
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.
CVE-2019-9794
A vulnerability was discovered where specific command line arguments are not properly discarded during Firefox invocation as a shell handler for URLs. This could be used to retrieve and execute files whose location is supplied through these command line arguments if Firefox is configured as the default URI handler for a given URI scheme in third party applications and these applications insufficiently sanitize URL data. *Note: This issue only affects Windows operating systems. Other operating systems are unaffected.*. This vulnerability affects Thunderbird < 60.6, Firefox ESR < 60.6, and Firefox < 66.
CVE-2019-11717
A vulnerability exists where the caret (“^”) character is improperly escaped constructing some URIs due to it being used as a separator, allowing for possible spoofing of origin attributes. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.
CVE-2019-11711
When an inner window is reused, it does not consider the use of document.domain for cross-origin protections. If pages on different subdomains ever cooperatively use document.domain, then either page can abuse this to inject script into arbitrary pages on the other subdomain, even those that did not use document.domain to relax their origin security. This vulnerability affects Firefox ESR < 60.8, Firefox < 68, and Thunderbird < 60.8.
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.