CVE-2023-51713Public exploitNetwork attack vector

Daemon crash via malformed FTP command parsing

Published Dec 22, 2023 · Updated Nov 3, 2025

Out-of-bounds read in ProFTPD before 1.3.8a allows remote attackers to crash the FTP daemon with a malformed command. make_ftp_cmd lets pr_str_get_word interpret quotes and backslashes in the command name, then uses the shortened word length to scan the remaining input buffer past its end. No authentication or user interaction is required; the demonstrated consequence is a daemon crash rather than data disclosure or code execution.

CVSS severity7.5
High
EPSS probability4.25%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in ProFTPD before 1.3.8a allows remote attackers to crash the FTP daemon with a malformed command. make_ftp_cmd lets pr_str_get_word interpret quotes and backslashes in the command name, then uses the shortened word length to scan the remaining input buffer past its end. No authentication or user interaction is required; the demonstrated consequence is a daemon crash rather than data disclosure or code execution.

The record

CVE
CVE-2023-51713
Published
Dec 22, 2023
Updated
Nov 3, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-125, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 22, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

7.5NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-125Out-of-bounds Read
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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