CVE-2025-4253Public exploitNetwork attack vector

Remote code execution via oversized HASH argument

Published May 4, 2025 · Updated May 6, 2025

Buffer overflow in the HASH handler of PCMan FTP Server 2.0.7 allows remote attackers to execute code via an FTP command. The public exploit supplies 2,006 bytes before overwriting EIP and appending x86 shellcode in the HASH argument. Exposure requires an FTP listener that permits the demonstrated anonymous session; successful exploitation runs attacker-controlled code in the server process.

CVSS severity9.8
Critical
EPSS probability0.70%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in the HASH handler of PCMan FTP Server 2.0.7 allows remote attackers to execute code via an FTP command. The public exploit supplies 2,006 bytes before overwriting EIP and appending x86 shellcode in the HASH argument. Exposure requires an FTP listener that permits the demonstrated anonymous session; successful exploitation runs attacker-controlled code in the server process.

The record

CVE
CVE-2025-4253
Published
May 4, 2025
Updated
May 6, 2025
Vendor
PCMan
Product
PCMan FTP Server
Classifications
CWE-119, CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 4, 2025CVE publishedPublication date reported by the CVE source.
  2. May 6, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=2.0.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

PCMan · PCMan FTP Serverversion=2.0.7

Published CVSS scores

7.5VulDBAV:N/AC:L/Au:N/C:P/I:P/A:P
6.9VulDBCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
9.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-119Improper Restriction of Operations within the Bounds of a Memory Buffer
CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
T1190Exploit Public-Facing Application

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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