How severe is CVE-2009-4051?

CVE-2009-4051 has a CVSS 2.0 base score of 5.0, rated medium severity.

Is CVE-2009-4051 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2009-4051?

CVE-2009-4051 affects Downstairs.dnsalias Home Ftp Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2009-4051?

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

When was CVE-2009-4051 published?

CVE-2009-4051 was published on 2009-11-23 and last updated on 2026-06-16.

CVE-2009-4051

CVE-2009-4051 is a medium-severity vulnerability in Downstairs.dnsalias Home Ftp Server 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-20.

Key facts

Severity: Medium (CVSS 2.0 base score 5.0)
EPSS exploit prediction: 6% (93rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Downstairs.dnsalias Home Ftp Server
Published: 2009-11-23
Last modified: 2026-06-16

Description

Home FTP Server 1.10.1.139 allows remote attackers to cause a denial of service (daemon outage) via multiple invalid SITE INDEX commands.

Frequently asked questions

What is CVE-2009-4051?: Home FTP Server 1.10.1.139 allows remote attackers to cause a denial of service (daemon outage) via multiple invalid SITE INDEX commands.
How severe is CVE-2009-4051?: CVE-2009-4051 has a CVSS 2.0 base score of 5.0, rated medium severity.
Is CVE-2009-4051 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 6% (93rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2009-4051?: CVE-2009-4051 affects Downstairs.dnsalias Home Ftp Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2009-4051?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2009-4051 published?: CVE-2009-4051 was published on 2009-11-23 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:downstairs.dnsalias:home_ftp_server:1.10.1.139:*:*:*:*:*:*:*

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