CVE-2007-4322

CVE-2007-4322 describes a denial-of-service vulnerability in BlockHosts versions prior to 2.0.4. The flaw stems from improper parsing of sshd and vsftpd log files, allowing remote attackers to inject arbitrary IP addresses into /etc/hosts.allow. This can be achieved by including an IP address string in the SSH client protocol version identification or the FTP username. The vulnerability has a CVSS score of 6.8, indicating a medium severity. It can be exploited remotely with medium attack complexity, potentially leading to a denial of service by blocking legitimate users. While the EPSS score is low, its FAUCET Risk Score is high at 82/100. There is no evidence of active exploitation, and no public exploit code (Metasploit, Nuclei, ExploitDB) is available. Despite this, the CVE has garnered significant community discussion, with 10 mentions, suggesting a degree of awareness among security professionals.