Improper Authentication Affecting fail2ban package, versions <0.8.3-2sid1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
1.3% (67th percentile)

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  • Snyk IDSNYK-ECHOLATEST-FAIL2BAN-20877230
  • published13 Oct 2026
  • disclosed13 Feb 2009

Introduced: 13 Feb 2009

CVE-2009-0362  (opens in a new tab)
CWE-287  (opens in a new tab)

How to fix?

Upgrade Echo:latest fail2ban to version 0.8.3-2sid1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream fail2ban package and not the fail2ban package as distributed by Echo. See How to fix? for Echo:latest relevant fixed versions and status.

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.

CVSS Base Scores

version 3.1