{"id":"CVE-2007-4321","url":"https://www.cyber-defence.io/tools/cve/CVE-2007-4321","generatedAt":"2026-10-27T18:46:01.047Z","title":"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…","description":"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.","published":"2007-08-14T00:17:00.000Z","lastModified":"2026-06-16T22:43:49.000Z","status":"Modified","sourceIdentifier":"cve@mitre.org","cvss":{"version":"2.0","score":6.8,"severity":"MEDIUM","vector":"AV:N/AC:M/Au:N/C:P/I:P/A:P"},"cwe":[],"affected":["fail2ban/fail2ban"],"epss":{"score":0.05748,"percentile":0.93015,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":1,"verified":true,"firstPublished":"2007-07-28","source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[{"edbId":30430,"kind":"exploit","title":"Fail2ban 0.8 - Remote Denial of Service","url":"https://www.exploit-db.com/exploits/30430","sourceUrl":"https://gitlab.com/exploit-database/exploitdb/-/blob/main/exploits/linux/dos/30430.txt","file":"exploits/linux/dos/30430.txt","published":"2007-07-28","added":"2007-07-28","updated":"2013-12-23","author":"Daniel B. Cid","type":"dos","platform":"linux","port":null,"verified":true,"codes":["CVE-2007-4321","OSVDB-42484"],"tags":null,"aliases":null,"applicationUrl":null,"screenshotUrl":null,"referenceUrl":"https://www.securityfocus.com/bid/25117/info"}]},"verdict":{"level":"high","text":"A public exploit is published in Exploit-DB (verified), so the technical barrier is gone even though the severity is medium and EPSS is 5.7%. Treat it as high on anything reachable from the internet."},"changes":[],"references":[{"url":"http://bugs.gentoo.org/show_bug.cgi?id=181214","source":"cve@mitre.org"},{"url":"http://osvdb.org/42484","source":"cve@mitre.org"},{"url":"http://secunia.com/advisories/23237","source":"cve@mitre.org"},{"url":"http://secunia.com/advisories/28374","source":"cve@mitre.org"},{"url":"http://security.gentoo.org/glsa/glsa-200707-13.xml","source":"cve@mitre.org"},{"url":"http://www.debian.org/security/2008/dsa-1456","source":"cve@mitre.org"},{"url":"http://www.ossec.net/en/attacking-loganalysis.html","source":"cve@mitre.org"},{"url":"http://www.securityfocus.com/bid/25117","source":"cve@mitre.org"},{"url":"http://bugs.gentoo.org/show_bug.cgi?id=181214","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://osvdb.org/42484","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/23237","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://secunia.com/advisories/28374","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://security.gentoo.org/glsa/glsa-200707-13.xml","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.debian.org/security/2008/dsa-1456","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.ossec.net/en/attacking-loganalysis.html","source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securityfocus.com/bid/25117","source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2007-4321","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}