VulnerabilityPublished 3 Jan 2024Updated 7 Nov 2025

CVE-2023-6004: Red Hat Enterprise Linux 8 · Injection

Affects Red Hat Enterprise Linux 8Source CVE Database V5

Not known to be exploited · CVSS 4.8 Medium.

Data as of 26 Oct 2026, 09:08 UTC

CVSS 3.1 base score

4.8Medium

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

EPSS: 0.4% chance of exploitation in 30 days – higher than 38% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: Low
Availability: Low

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

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
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: 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 impacted component.
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 on 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

Disclosed: evidence found.
CVE published 3 Jan 2024
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 26 Oct 2026.

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

AI-suggested

1. Apply official patches from Red Hat as soon as they become available to address the vulnerability in libssh. 2. Until patches are applied, restrict or disable the use of ProxyCommand and ProxyJump features in SSH client configurations where feasible. 3. Implement strict input validation and sanitization for any hostname parameters used in ProxyCommand or ProxyJump to prevent injection of malicious code. 4. Enforce least privilege principles to limit local user permissions, reducing the potential for exploitation by low-privileged users. 5. Educate users about the risks of connecting to untrusted hosts or using unverified SSH configurations that may trigger this vulnerability. 6. Monitor SSH logs and system behavior for unusual command executions or proxy usage patterns indicative of exploitation attempts. 7. Employ endpoint detection and response (EDR) tools to detect suspicious activities related to SSH command injections. 8. Review and harden SSH client configurations across the organization, ensuring that only necessary features are enabled and properly secured.

Description

A flaw was found in libssh. By utilizing the ProxyCommand or ProxyJump feature, users can exploit unchecked hostname syntax on the client. This issue may allow an attacker to inject malicious code into the command of the features mentioned through the hostname parameter.

Impact

For European organizations, the vulnerability poses a moderate risk primarily to systems running Red Hat Enterprise Linux 8 that utilize SSH ProxyCommand or ProxyJump features. Exploitation could allow attackers with limited local privileges to inject malicious commands, potentially leading to unauthorized command execution, data leakage, or service disruption. This could affect enterprise servers, development environments, and critical infrastructure systems relying on secure SSH connections. The requirement for user interaction and local privileges reduces the likelihood of widespread automated exploitation but does not eliminate targeted attacks, especially in environments with less stringent access controls. Confidentiality, integrity, and availability could be partially compromised, impacting business operations, data security, and compliance with European data protection regulations. Organizations in sectors such as finance, government, telecommunications, and energy, which often deploy RHEL 8 in critical roles, may face higher operational risks if this vulnerability is exploited.

References

Community reviews

Loading reviews…

Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 11 Nov 2025, 19:57 UTC

Technical details

References

Community reviews

Related threats