How severe is CVE-2007-6263?

CVE-2007-6263 has a CVSS 2.0 base score of 9.3, rated critical severity.

Is CVE-2007-6263 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2007-6263?

CVE-2007-6263 affects Netkit-ftp Netkit Ftp. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2007-6263?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2007-6263 published?

CVE-2007-6263 was published on 2007-12-06 and last updated on 2026-06-16.

CVE-2007-6263

CVE-2007-6263 is a critical-severity vulnerability in Netkit-ftp Netkit Ftp with a CVSS 2.0 base score of 9.3. 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: Critical (CVSS 2.0 base score 9.3)
EPSS exploit prediction: 2% (83rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Netkit-ftp Netkit Ftp
Published: 2007-12-06
Last modified: 2026-06-16

Description

The dataconn function in ftpd.c in netkit ftpd (netkit-ftpd) 0.17, when certain modifications to support SSL have been introduced, calls fclose on an uninitialized file stream, which allows remote attackers to cause a denial of service (daemon crash) and possibly have unspecified other impact via some types of FTP over SSL protocol behavior, as demonstrated by breaking a passive FTP DATA connection in a way that triggers an error in the server's SSL_accept function. NOTE: the netkit ftp issue is covered by CVE-2007-5769.

Frequently asked questions

What is CVE-2007-6263?: The dataconn function in ftpd.c in netkit ftpd (netkit-ftpd) 0.17, when certain modifications to support SSL have been introduced, calls fclose on an uninitialized file stream, which allows remote attackers to cause a denial of service (daemon crash) and possibly have unspecified other impact via some types of FTP over SSL protocol behavior, as demonstrated by breaking a passive FTP DATA connection in a way that triggers an error in the server's SSL_accept function. NOTE: the netkit ftp issue is covered by CVE-2007-5769.
How severe is CVE-2007-6263?: CVE-2007-6263 has a CVSS 2.0 base score of 9.3, rated critical severity.
Is CVE-2007-6263 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2007-6263?: CVE-2007-6263 affects Netkit-ftp Netkit Ftp. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2007-6263?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2007-6263 published?: CVE-2007-6263 was published on 2007-12-06 and last updated on 2026-06-16.

References

Affected products (1)

cpe:2.3:a:netkit-ftp:netkit_ftp:0.17:*:*:*:*:*:*:*

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