CVE-2026-42391

An unauthenticated attacker can send an IMAP ID command with a very large number of parameters before logging in, which causes memory and CPU usage to grow disproportionately. The login process can be terminated by the out-of-memory handling, which also terminates all other connections handled by...

CVE-2026-42391

Open-Xchange Dovecot is vulnerable to a denial-of-service attack in its imap-login process. An unauthenticated attacker can send an IMAP ID command with a very large number of parameters before authentication, causing disproportionate memory and CPU consumption . The resulting out-of-memory termi...