CVE-2025-5356Public exploitNetwork attack vector

Unauthenticated memory corruption via oversized BYE command

Published May 30, 2025 · Updated May 30, 2025

A buffer overflow in FreeFloat FTP Server 1.0 allows remote attackers to corrupt memory by sending an oversized BYE command. The BYE command handler copies an attacker-controlled argument without validating its length, causing data to exceed the destination buffer. No authentication or user interaction is required; the overflow can crash the FTP service and corrupt control-flow data in its process.

CVSS severity6.9
Medium
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

A buffer overflow in FreeFloat FTP Server 1.0 allows remote attackers to corrupt memory by sending an oversized BYE command. The BYE command handler copies an attacker-controlled argument without validating its length, causing data to exceed the destination buffer. No authentication or user interaction is required; the overflow can crash the FTP service and corrupt control-flow data in its process.

The record

CVE
CVE-2025-5356
Published
May 30, 2025
Updated
May 30, 2025
Vendor
Freefloat AB
Product
Freefloat FTP Server
Classifications
CWE-119, CWE-120, T1190
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 30, 2025CVE publishedPublication date reported by the CVE source.
  2. May 30, 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

6.9VulDB CNACVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N
7.5VulDB CNAAV:N/AC:L/Au:N/C:P/I:P/A:P
7.3VulDB CNACVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
7.3VulDB CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L
9.8NVDCVSS: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')
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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