Security Resilience

CVE-2023-51713

Memory Safety in Proftpd ≤ 1.3.8a

Public PoCMemory Safety
Published
22 December 2023
Modified
03 November 2025
Patch / advisory
View advisory
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.042 91th percentile
Risk Priority 83 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-51713 is a high-severity Out-of-bounds Read (CWE-125) vulnerability in Proftpd Proftpd. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Data Obfuscation (T1001); ranked in the top 9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

ProFTPD versions prior to 1.3.8a contain a one-byte out-of-bounds read in the make_ftp_cmd function within main.c. The flaw stems from incorrect handling of quote and backslash characters in FTP command processing and is tracked as CWE-125. It produces a daemon crash with no confidentiality or integrity impact, corresponding to a CVSS 3.1 base score of 7.5.

An unauthenticated remote attacker can send a crafted FTP command containing specific quote or backslash sequences to trigger the read. Successful exploitation results only in denial of service through an immediate process termination; no code execution or data exposure has been demonstrated.

The project’s NEWS file and associated GitHub issue confirm that the defect is resolved in release 1.3.8a. Administrators are advised to upgrade ProFTPD instances to that version or later.

The CVE carries an EPSS score that reached a peak of 0.7339, indicating notable exploitation interest after public disclosure.

EU & UK References

Vulnerability Data

make_ftp_cmd in main.c in ProFTPD before 1.3.8a has a one-byte out-of-bounds read, and daemon crash, because of mishandling of quote/backslash semantics.

CWE(s)
CWE-125

Related Threats

MITRE ATT&CK Enterprise Techniques

T1001 Data Obfuscation Command And Control
Adversaries may obfuscate command and control traffic to make it more difficult to detect.
attack.mitre.org →
T1001.002 Steganography Command And Control
Adversaries may use steganographic techniques to hide command and control traffic to make detection efforts more difficult.
attack.mitre.org →
T1003.002 Security Account Manager Credential Access
Adversaries may attempt to extract credential material from the Security Account Manager (SAM) database either through in-memory techniques or through the Windows Registry where the SAM database is stored.
attack.mitre.org →
T1003.003 NTDS Credential Access
Adversaries may attempt to access or create a copy of the Active Directory domain database in order to steal credential information, as well as obtain other information about domain members such as devices, users, and access rights.
attack.mitre.org →
T1003.004 LSA Secrets Credential Access
Adversaries with SYSTEM access to a host may attempt to access Local Security Authority (LSA) secrets, which can contain a variety of different credential materials, such as credentials for service accounts.
attack.mitre.org →
T1003.006 DCSync Credential Access
Adversaries may attempt to access credentials and other sensitive information by abusing a Windows Domain Controller's application programming interface (API)(Citation: Microsoft DRSR Dec 2017) (Citation: Microsoft GetNCCChanges) (Citati…
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-61845Shared CWE-125
CVE-2026-21340Shared CWE-125
CVE-2024-37401Shared CWE-125
CVE-2025-20922Shared CWE-125
CVE-2025-54260Shared CWE-125
CVE-2024-47454Shared CWE-125
CVE-2024-20771Shared CWE-125
CVE-2025-12441Shared CWE-125
CVE-2026-25209Shared CWE-125
CVE-2026-7995Shared CWE-125

Affected Assets

proftpd
proftpd
≤ 1.3.8a

Mitigating Controls

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

ID.RA-01 partial match
blocks

Vulnerability scanning and recording can discover instances of out-of-bounds reads after code is deployed.

PR.PS-02 partial match
blocks

Routine patching replaces vulnerable code containing out-of-bounds read flaws.

PR.PS-06 partial match
blocks

Secure-development practices such as bounds checking and memory-safe languages directly prevent out-of-bounds reads.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

A.5.14 Information transfer partial match
removes
A.5.15 Access control partial match
removes
A.5.16 Identity management partial match
removes
A.5.17 Authentication information partial match
removes
A.5.18 Access rights partial match
removes
A.8.10 Information deletion partial match
removes

References