CVE-2024-0723VulnerabilityPublished 19 Jan 2024Updated 30 May 2025

CVE-2024-0723: freeSSHd · Denial of Service

Affects freeSSHdSource CVE Database V5

Not known to be exploited · public exploit available (Exploit-DB) · CVSS 5.3 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

5.3Medium

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

EPSS: 3.6% chance of exploitation in 30 days – higher than 89% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, 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: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
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 impacted component 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 impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

t = 0 is the CVE’s publication on cve.org

Disclosed: evidence found.
CVE published 19 Jan 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: evidence found.
1 Exploit-DB entry, 1.4 years after disclosure
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

CVE ID reserved
by VulDB
2024-01-1909:53Z, 7 hours before disclosure
CVE published
on cve.org
2024-01-1916:31Z, t = 0
First Exploit-DB entry (opens in a new tab)
freeSSHd 1.0.9 - Denial of Service (DoS)
2025-06-26, 1.4 years after disclosure

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
n/a freeSSHd	Affected =1.0.9	Fixed in–

AI-suggested

Given the absence of an official patch, European organizations should implement the following specific mitigations: 1) Immediately assess and inventory all Windows servers running freeSSHd version 1.0.9 to identify exposed instances. 2) Restrict network access to freeSSHd services using firewall rules or network segmentation to limit exposure to trusted IP addresses only, reducing the attack surface. 3) Consider disabling freeSSHd temporarily on non-critical systems until a patch or update is available. 4) Where possible, replace freeSSHd with alternative, actively maintained SSH server software that is not affected by this vulnerability. 5) Monitor network traffic and system logs for unusual connection attempts or service disruptions indicative of exploitation attempts. 6) Prepare incident response plans to quickly restore service availability in case of a DoS attack. 7) Stay informed on vendor updates or community patches addressing this vulnerability and apply them promptly once available.

Description

A vulnerability was found in freeSSHd 1.0.9 on Windows. It has been classified as problematic. This affects an unknown part. The manipulation leads to denial of service. It is possible to initiate the attack remotely. The exploit has been disclosed to the public and may be used. The associated identifier of this vulnerability is VDB-251547.

Impact

For European organizations, the primary impact of CVE-2024-0723 is the potential disruption of critical services relying on freeSSHd for secure remote access. Organizations using freeSSHd 1.0.9 on Windows servers may experience denial of service conditions, leading to loss of availability of SSH services. This could affect IT operations, remote management, and automated deployment or monitoring systems. While the vulnerability does not compromise data confidentiality or integrity, the loss of availability can have cascading effects, especially in sectors requiring high uptime such as finance, healthcare, and critical infrastructure. The medium severity rating suggests that while the risk is not critical, it should not be ignored, particularly in environments where freeSSHd is exposed to untrusted networks. European organizations with legacy or niche deployments of freeSSHd are at risk of operational disruption, which could translate into financial losses or compliance issues if service level agreements are breached.

Summary

CVE-2024-0723 is a vulnerability identified in freeSSHd version 1.0.9, a Windows-based SSH server application. The vulnerability is classified under CWE-404, which corresponds to an improper resource shutdown or release issue. This flaw allows an unauthenticated remote attacker to trigger a denial of service (DoS) condition by manipulating an unspecified component of the freeSSHd service. The vulnerability can be exploited remotely without requiring any user interaction or privileges, making it accessible to any attacker with network access to the affected server. The impact of exploitation is limited to availability, as the vulnerability does not affect confidentiality or integrity. The CVSS v3.1 base score is 5.3 (medium severity), with vector AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L, indicating network attack vector, low attack complexity, no privileges or user interaction required, and impact limited to availability. No patches or fixes have been disclosed yet, and no known exploits are reported in the wild at this time. The vulnerability disclosure date is January 19, 2024. Given freeSSHd's role as an SSH server, successful exploitation could disrupt remote administrative access or automated processes relying on SSH connectivity, potentially causing operational downtime or service interruptions.

CWE-404Improper Resource Shutdown or Release (opens in a new tab)
Class weaknessLikelihood of exploit: Medium
The product does not release or incorrectly releases a resource before it is made available for re-use.
Requirements · Language Selection
Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
Implementation
It is good practice to be responsible for freeing all resources you allocate and to be consistent with how and where you free memory in a function. If you allocate memory that you intend to free upon completion of the function, you must be sure to free the memory at all exit points for that function including error…
Implementation
Memory should be allocated/freed using matching functions such as malloc/free, new/delete, and new[]/delete[].
Attack patterns
TCP Fragmentation (opens in a new tab)
UDP Fragmentation (opens in a new tab)
ICMP Fragmentation (opens in a new tab)
BlueSmacking (opens in a new tab)
Flooding (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

Timeline

What to do

Affected software

Description

AI analysisMachine-generated, updated 8 Jul 2025, 16:42 UTC

Public exploits and detection1 Exploit-DB entry

WeaknessesCWE-404

Technical details

References

Community reviews

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