CVE-2025-5666VulnerabilityPublished 5 Jun 2025

CVE-2025-5666: 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: 0.6% chance of exploitation in 30 days – higher than 51% 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 5 Jun 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	Fixed in–

AI-suggested

1. Immediate identification and inventory of all FreeFloat FTP Server instances, focusing on version 1.0 deployments. 2. If possible, disable or restrict access to the FTP service, especially from untrusted networks or the internet. 3. Implement network-level controls such as firewall rules to limit access to the FTP server to trusted IP addresses only. 4. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures or anomaly detection capable of identifying malformed XMKD commands or buffer overflow attempts. 5. Monitor FTP server logs for unusual or suspicious XMKD command usage patterns. 6. Consider replacing FreeFloat FTP Server 1.0 with a more secure, actively maintained FTP server solution. 7. If patch or vendor updates become available, prioritize immediate application. 8. Employ network segmentation to isolate FTP servers from critical internal systems to limit lateral movement in case of compromise. 9. Educate IT and security teams about this vulnerability and ensure incident response plans include steps for FTP server compromise scenarios.

Description

A vulnerability was found in FreeFloat FTP Server 1.0. It has been declared as critical. Affected by this vulnerability is an unknown functionality of the component XMKD Command Handler. The manipulation leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.

Impact

For European organizations, the impact of this vulnerability can be substantial, particularly for those relying on FreeFloat FTP Server 1.0 for file transfer operations. Successful exploitation could lead to unauthorized remote code execution, allowing attackers to gain control over affected systems, exfiltrate sensitive data, disrupt services, or pivot within internal networks. This could compromise confidentiality, integrity, and availability of critical business data and systems. Sectors such as finance, healthcare, manufacturing, and government agencies that handle sensitive or regulated data and use FTP servers for data exchange are at higher risk. Additionally, the vulnerability could be leveraged to launch further attacks, including ransomware or espionage campaigns. The medium CVSS score may underestimate the real-world impact if exploit code is developed, especially since no authentication or user interaction is required. The absence of patches means organizations must rely on network-level mitigations and monitoring to reduce risk. The public disclosure increases the likelihood of attackers developing exploits targeting European entities, especially those with exposed FTP services.

References

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 7 Jul 2025, 15:56 UTC

Technical details

References

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