A security issue has been found in fail2ban before version 0.11.3. The "mail" command from the mailutils package used in mail actions like mail-whois can execute commands if unescaped sequences (\n~) are available in "foreign" input (for instance in whois output).
A security issue has been found in fail2ban before version 0.11.3. The "mail" command from the mailutils package used in mail actions like mail-whois can execute commands if unescaped sequences (\n~) are available in "foreign" input (for instance in whois output).
https://github.com/fail2ban/fail2ban/security/advisories/GHSA-m985-3f3v-cwmm https://github.com/fail2ban/fail2ban/commit/410a6ce5c80dd981c22752da034f2529b5eee844
Workaround ========== The way for users to fix or remediate the vulnerability without upgrading would be to avoid the usage of action mail-whois or to patch it manually.
Vulmon