Auth bypass in Fail2ban

CVE-2009-0362

filter.d/wuftpd.conf in Fail2ban 0.8.3 uses an incorrect regular expression that allows remote attackers to cause a denial of service (forced authentication failures) via a crafted reverse-resolved DNS name (rhost) entry that contains a substring that is interpreted as an IP address, a different vulnerability than CVE-2007-4321.

Vulnerability class: Broken Authentication

EPSS: 0.013 (67.5th percentile) — read the EPSS interpretation.

Affected products

Fail2ban — versions 0.8.3
N/a — versions n/a

Weakness classification (CWE)

CWE-287 — Improper Authentication

References

cve@mitre.org (x_refsource_SECUNIA, Vendor Advisory, third-party-advisory)
cve@mitre.org (vdb-entry, x_refsource_BID)
cve@mitre.org (x_refsource_CONFIRM, Exploit)