View at Official debian advisory, NVD, CVE.org · CVE detail
Freshness: upstream tracker timestamp is available; use API updated time as primary recency signal.
CVE-2007-4321 medium priority: Debian including 1 source packages (fail2ban), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.
fail2ban 0.8 and earlier does not properly parse sshd log files, which allows remote attackers to add arbitrary hosts to the /etc/hosts.deny file and cause a denial of service by adding arbitrary IP addresses to the sshd log file, as demonstrated by logging in via ssh with a client protocol version identification containing an IP address string, a different vector than CVE-2006-6302.