CVE-2025-4791Public exploitNetwork attack vector

Remote memory corruption via oversized HASH argument

Published May 16, 2025 · Updated May 16, 2025

Buffer overflow in the HASH command handler in FreeFloat FTP Server 1.0 allows remote attackers to corrupt process memory via FTP. The handler copies an attacker-controlled HASH argument without checking its length against the destination buffer. No authentication or user interaction is required; successful exploitation overwrites process memory and can crash the FTP service.

CVSS severity9.8
Critical
EPSS probability0.73%
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 command handler in FreeFloat FTP Server 1.0 allows remote attackers to corrupt process memory via FTP. The handler copies an attacker-controlled HASH argument without checking its length against the destination buffer. No authentication or user interaction is required; successful exploitation overwrites process memory and can crash the FTP service.

The record

CVE
CVE-2025-4791
Published
May 16, 2025
Updated
May 16, 2025
Vendor
Freefloat AB
Product
Freefloat FTP Server
Classifications
CWE-119, CWE-120, CWE-787, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 16, 2025CVE publishedPublication date reported by the CVE source.
  2. May 16, 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?

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

  1. Affected versionversion=1.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Freefloat AB · Freefloat FTP Serverversion=1.0

Published CVSS scores

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
7.3VulDBCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
7.5VulDBAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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.

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')
CWE-787Out-of-bounds Write
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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