The 'Copy as cURL' feature of Devtools' network tab did not properly escape the HTTP method of a request, which can be controlled by the website. If a user used the 'Copy as Curl' feature and pasted the command into a terminal, it could have resulted in command injection and arbitrary command execution. This vulnerability affects Thunderbird < 68.6, Firefox < 74, Firefox < ESR68.6, and Firefox ESR < 68.6.

References

• https://nvd.nist.gov/vuln/detail/CVE-2020-6811
• https://bugzilla.mozilla.org/show_bug.cgi?id=1607742
• https://usn.ubuntu.com/4328-1/
• https://usn.ubuntu.com/4335-1/
• https://www.mozilla.org/security/advisories/mfsa2020-08/
• https://www.mozilla.org/security/advisories/mfsa2020-09/
• https://www.mozilla.org/security/advisories/mfsa2020-10/