Roundcube Webmail before 1.6.20 and 1.7.x before 1.7.5 are affected by IMAP command injection. A remote authenticated attacker can exploit this via CRLF sequences injected into the _uid parameter of the mail/headers and mail/viewsource actions to execute arbitrary IMAP commands.
https://roundcube.net/news/2026/10/19/security-updates-1.6.20-and-1.7.5
https://github.com/roundcube/roundcubemail/releases/tag/1.7.5
https://github.com/roundcube/roundcubemail/releases/tag/1.6.20
https://github.com/roundcube/roundcubemail/commit/f62879defc0330ae240c72b83b2d00a8ab337447
https://github.com/roundcube/roundcubemail/commit/bf5bc0266a8cd16be6b640409e64a6c6c2705049
https://github.com/roundcube/roundcubemail/commit/004adaaeca4f6799715a54d12e3f657f19efcc9a