CVE-2025-5221VulnerabilityPublished 27 May 2025

CVE-2025-5221: FreeFloat FTP Server · Buffer Overflow

Affects FreeFloat FTP ServerSource CVE Database V5

Not known to be exploited · CVSS 6.9 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 4.0 base score

6.9Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.7% chance of exploitation in 30 days – higher than 54% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: None
User Interaction: None
Vulnerable system confidentiality: Low
Vulnerable system integrity: Low
Vulnerable system availability: Low
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, up to and including the entire Internet. Such a vulnerability is often termed “remotely exploitable” and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files of the vulnerable system to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without interaction from any human user, other than the attacker.
Vulnerable system confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the Vulnerable System.
Vulnerable system integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact to the Vulnerable System.
Vulnerable system availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the Vulnerable System are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 27 May 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
FreeFloat FTP Server	Affected =1.0.0	Fixed in–

AI-suggested

Given the absence of an official patch, European organizations should implement immediate compensating controls. These include restricting network access to the FreeFloat FTP Server by implementing firewall rules to limit connections to trusted IP addresses only. Disabling or restricting the use of the QUOTE command on the FTP server, if configurable, can mitigate the attack vector. Organizations should consider replacing FreeFloat FTP Server 1.0.0 with a more secure and actively maintained FTP server solution. Network segmentation should be employed to isolate FTP servers from critical internal systems. Continuous monitoring of FTP server logs for anomalous QUOTE command usage or unexpected traffic patterns is recommended to detect potential exploitation attempts. If possible, deploying intrusion detection/prevention systems (IDS/IPS) with signatures targeting this vulnerability can provide additional defense. Finally, organizations should maintain an incident response plan to quickly address any signs of compromise related to this vulnerability.

Description

A vulnerability was found in FreeFloat FTP Server 1.0.0. It has been classified as critical. This affects an unknown part of the component QUOTE Command Handler. The manipulation leads to buffer overflow. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used.

Impact

For European organizations, the impact of CVE-2025-5221 depends largely on the deployment of FreeFloat FTP Server 1.0.0 within their infrastructure. Organizations using this FTP server version, particularly those exposing it to the internet or untrusted networks, face risks including unauthorized remote code execution, data leakage, or service disruption. This could lead to compromise of sensitive data, interruption of business operations, and potential lateral movement within networks. Given the FTP protocol's common use for file transfers, exploitation could facilitate exfiltration of confidential files or insertion of malicious payloads. The medium CVSS score suggests that while the vulnerability is serious, it may not lead to full system compromise in all cases. However, the absence of authentication and user interaction requirements increases the likelihood of automated exploitation attempts. European entities in sectors with high reliance on FTP services, such as manufacturing, logistics, or legacy system environments, may be particularly vulnerable. Additionally, compliance with GDPR and other data protection regulations means that exploitation leading to data breaches could result in significant legal and financial consequences.

Summary

CVE-2025-5221 is a buffer overflow vulnerability identified in FreeFloat FTP Server version 1.0.0, specifically within the QUOTE Command Handler component. The vulnerability arises due to improper handling of input data in the QUOTE command, allowing an attacker to send specially crafted commands that overflow a buffer. This overflow can corrupt memory, potentially enabling remote code execution or causing a denial of service. The vulnerability is remotely exploitable without requiring authentication or user interaction, as indicated by the CVSS vector (AV:N/AC:L/PR:N/UI:N). The CVSS 4.0 base score is 6.9, categorized as medium severity, reflecting the potential for partial impact on confidentiality, integrity, and availability, but with some limitations on the scope and impact. No known exploits are currently reported in the wild, and no patches or mitigations have been published by the vendor at the time of disclosure. The vulnerability affects only version 1.0.0 of FreeFloat FTP Server, which is a niche FTP server product. The lack of authentication requirement and remote exploitability make this a significant risk for exposed servers running this specific version, especially if accessible from untrusted networks.

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 11 Jul 2025, 10:47 UTC

Technical details

References

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