CVE-2007-4323: Denyhosts

Medium severity, CVSS 6.8. EPSS: 1.5% chance of exploitation in the next 30 days.

DenyHosts 2.6 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-2006-6301.

Affected products

• Denyhosts Denyhosts: version 2.6 only

Published 2007-08-14. Last modified 2026-06-16.