CVE-2006-6301
DenyHosts 2.5 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 login name containing certain strings with an IP address, which is not properly handled by a regular expression.
Key facts
- CVSS score
- 5.0 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:L/Au:N/C:N/I:N/A:P- EPSS score
- 1.9% (80th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2006-6284)
- Published
- December 6, 2006
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2006-6284 in the EU Vulnerability Database. Last updated in EUVD on August 7, 2024.
View on the EU Vulnerability DatabaseAffected products
- denyhosts / denyhosts
References
- http://bugs.gentoo.org/show_bug.cgi?id=157163(Exploit)
- http://secunia.com/advisories/23236(Vendor Advisory)
- http://secunia.com/advisories/23603(Vendor Advisory)
- http://security.gentoo.org/glsa/glsa-200701-01.xml
- http://www.securityfocus.com/bid/21468
- http://www.vupen.com/english/advisories/2006/4876
- https://exchange.xforce.ibmcloud.com/vulnerabilities/30761
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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