Denial of Service Vulnerability in denyhosts by Fail2Ban

CVE-2013-6890

Summary

denyhosts 2.6 contains a vulnerability stemming from the incorrect implementation of a regular expression during the analysis of authentication logs. This flaw enables remote attackers to exploit the system by sending specially crafted login names, ultimately leading to a denial of service through erroneous IP address blocking. As a result, legitimate users may find themselves unable to access resources due to legitimate requests being denied.

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