No exploitation reportedFix available

CVE-1999-1568

Q: Is CVE-1999-1568 actively exploited?

Active exploitation of CVE-1999-1568 has not been confirmed. Its EPSS score was 2.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

Q: What is the CVSS score for CVE-1999-1568?

CVE-1999-1568 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

No exploitation reported by the sources we read.

Published1999-01-01
Fixed in2.4.1
WeaknessCWE-193

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Off-by-one error in NcFTPd FTP server before 2.4.1 allows a remote attacker to cause a denial of service (crash) via a long PORT command.

Timeline

dates in UTC

1999-01-0105:00CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-1999-1568?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-1999-1568?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Ncftp ncftpd server

Branch	Affected	Fixed in	Source
2.4	< 2.4.1	2.4.1	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Update Ncftp ncftpd server to 2.4.1

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CISA-ADPSSVC decisionnone2025-01-16
OpenCVESSVC decisionnone—
CISA-ADPCVSS 3.17.52025-01-16
NVDCVSS 3.17.5read 2026-10-23
NVDCVSS 2.05read 2026-10-23
CISA-ADPweakness (CWE)CWE-1932025-01-16
NVDweakness (CWE)CWE-193read 2026-10-23
FIRST EPSSEPSS score2.3 %2026-10-23

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 1999-01-01
Last Modified: 2026-06-16
NVD status: Modified

Frequently asked questions

What is CVE-1999-1568?

Off-by-one error in NcFTPd FTP server before 2.4.1 allows a remote attacker to cause a denial of service (crash) via a long PORT command.

Is CVE-1999-1568 actively exploited?

Active exploitation of CVE-1999-1568 has not been confirmed. Its EPSS score was 2.3% on 2026-10-23, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-1999-1568?

CVE-1999-1568 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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