CVE-2020-6799: Mozilla Firefox
High severity, CVSS 8.8. EPSS: 1.5% chance of exploitation in the next 30 days.
Command line arguments could have been injected during Firefox invocation as a shell handler for certain unsupported file types. This required Firefox to be configured as the default handler for a given file type and for a file downloaded to be opened in a third party application that insufficiently sanitized URL data. In that situation, clicking a link in the third party application could have been used to retrieve and execute files whose location was supplied through command line arguments. Note: This issue only affects Windows operating systems and when Firefox is configured as the default handler for non-default filetypes. Other operating systems are unaffected. This vulnerability affects Firefox < 73 and Firefox < ESR68.5.
Affected products
Published 2020-03-02. Last modified 2026-06-17.