CVE-2020-6811: Canonical Ubuntu Linux

High severity, CVSS 8.8. EPSS: 3.3% chance of exploitation in the next 30 days.

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.

Affected products

• Canonical Ubuntu Linux: version 16.04 only; version 18.04 only; version 19.10 only
• Mozilla Firefox: before 74.0 (fixed in 74.0)
• Mozilla Firefox ESR: before 68.6.0 (fixed in 68.6.0)
• Mozilla Thunderbird: before 68.6.0 (fixed in 68.6.0)

Published 2020-03-25. Last modified 2026-06-17.