How severe is CVE-2013-6890?

CVE-2013-6890 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2013-6890 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2013-6890?

CVE-2013-6890 primarily affects Phil Schwartz Denyhosts. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2013-6890?

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

When was CVE-2013-6890 published?

CVE-2013-6890 was published on 2013-12-23 and last updated on 2026-06-17.

CVE-2013-6890

CVE-2013-6890 is a medium-severity vulnerability in Phil Schwartz Denyhosts with a CVSS 2.0 base score of 5.0. 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 5.0)
EPSS exploit prediction: 9% (95th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-287
Affected product: Phil Schwartz Denyhosts
Published: 2013-12-23
Last modified: 2026-06-17

Description

denyhosts 2.6 uses an incorrect regular expression when analyzing authentication logs, which allows remote attackers to cause a denial of service (incorrect block of IP addresses) via crafted login names.

Frequently asked questions

What is CVE-2013-6890?: denyhosts 2.6 uses an incorrect regular expression when analyzing authentication logs, which allows remote attackers to cause a denial of service (incorrect block of IP addresses) via crafted login names.
How severe is CVE-2013-6890?: CVE-2013-6890 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2013-6890 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 9% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2013-6890?: CVE-2013-6890 primarily affects Phil Schwartz Denyhosts. In total, 5 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2013-6890?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2013-6890 published?: CVE-2013-6890 was published on 2013-12-23 and last updated on 2026-06-17.

References

Affected products (5)

cpe:2.3:o:debian:debian_linux:6.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:7.1:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:*:*:*:*:*:*:*:*
cpe:2.3:a:phil_schwartz:denyhosts:2.6:*:*:*:*:*:*:*

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