How severe is CVE-2009-0362?

CVE-2009-0362 has a CVSS 2.0 base score of 4.0, rated medium severity.

Is CVE-2009-0362 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-0362?

CVE-2009-0362 affects Fail2ban. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-0362?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2009-0362 published?

CVE-2009-0362 was published on 2009-02-13 and last updated on 2026-06-16.

CVE-2009-0362

CVE-2009-0362 is a medium-severity vulnerability in Fail2ban with a CVSS 2.0 base score of 4.0. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-287.

Key facts

Severity: Medium (CVSS 2.0 base score 4.0)
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Fail2ban
Published: 2009-02-13
Last modified: 2026-06-16

Description

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.

Frequently asked questions

What is 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.
How severe is CVE-2009-0362?: CVE-2009-0362 has a CVSS 2.0 base score of 4.0, rated medium severity.
Is CVE-2009-0362 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-0362?: CVE-2009-0362 affects Fail2ban. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-0362?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-0362 published?: CVE-2009-0362 was published on 2009-02-13 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:fail2ban:fail2ban:0.8.3:*:*:*:*:*:*:*

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Other CWE-287 (Improper Authentication) vulnerabilities

CVE-2026-45480 — Critical (CVSS 10.0): Improper authentication in Azure Active Directory allows an unauthorized attacker to elevate privileges over a network.
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CVE-2026-10611 — Critical (CVSS 10.0): An authentication bypass vulnerability exists in MISP when LDAP mixed authentication is enabled with OTP enforcement.…
CVE-2026-47280 — Critical (CVSS 10.0): Improper authentication in Azure Resource Manager (ARM) allows an unauthorized attacker to elevate privileges over a…
CVE-2026-42822 — Critical (CVSS 10.0): Improper authentication in Azure Local Disconnected Operations allows an unauthorized attacker to elevate privileges…
CVE-2026-20182 — Critical (CVSS 10.0): May 2026: This security advisory provides the details and fix information for a vulnerability that was discovered and…

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