CVE-2023-3961VulnerabilityPublished 3 Nov 2023Updated 20 Nov 2025

CVE-2023-3961: Red Hat Enterprise Linux 8 · Path Traversal

Affects Red Hat Enterprise Linux 8Source CVE Database V5

Not known to be exploited · CVSS 9.1 Critical.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

9.1Critical

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

EPSS: 2.6% chance of exploitation in 30 days – higher than 85% 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:H/A:H

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

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: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 3 Nov 2023
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 2026-10-26.

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

To mitigate CVE-2023-3961, European organizations should prioritize applying official patches from Red Hat as soon as they become available. In the interim, administrators should restrict network access to Samba services using firewall rules or network segmentation to limit exposure to untrusted networks. Disable or restrict SMB services if not required, and monitor Samba logs for unusual pipe name requests or connection attempts that include directory traversal patterns. Employ host-based intrusion detection systems to detect anomalous socket connections. Additionally, review and harden Unix domain socket permissions to prevent unauthorized access. Implement strict access controls and consider deploying application-layer firewalls or proxies that can sanitize or block malicious SMB requests. Regularly audit Samba configurations and update to the latest supported versions to benefit from security improvements. Finally, incorporate this vulnerability into incident response plans to ensure rapid detection and remediation if exploitation is suspected.

Description

CVE-2023-3961 is a critical path traversal vulnerability in Samba on Red Hat Enterprise Linux 8 that allows unauthenticated remote attackers to connect to unauthorized Unix domain sockets by sending crafted pipe names containing directory traversal sequences. This flaw arises from insufficient sanitization of client pipe names, enabling SMB clients to potentially access services outside the intended private directory with root privileges. Exploitation could lead to unauthorized access, service compromise, or crashes. The vulnerability has a CVSS score of 9.1, indicating high impact on integrity and availability without requiring authentication or user interaction. Although no known exploits are currently reported in the wild, the risk is significant due to the ease of exploitation and the critical nature of Samba in enterprise environments. European organizations using Red Hat Enterprise Linux 8 with Samba are at risk, especially those in countries with large enterprise Linux deployments and critical infrastructure. Immediate patching and strict network-level controls are recommended to mitigate this threat.

Impact

For European organizations, this vulnerability presents a severe risk to systems running Red Hat Enterprise Linux 8 with Samba enabled. Exploitation could lead to unauthorized access to critical system services, potentially allowing attackers to escalate privileges to root or disrupt essential services, impacting business continuity and data integrity. Organizations in sectors such as finance, government, telecommunications, and critical infrastructure are particularly vulnerable due to their reliance on secure and stable Linux server environments. The ability to exploit this vulnerability remotely without authentication increases the attack surface, making it attractive for threat actors targeting European enterprises. Additionally, disruption or compromise of Samba services could affect file sharing and authentication mechanisms, leading to broader operational impacts. Given the critical CVSS rating and the central role of Samba in many enterprise networks, the potential for significant confidentiality, integrity, and availability damage is high.

Summary

CVE-2023-3961 is a path traversal vulnerability found in the Samba component of Red Hat Enterprise Linux 8. Samba uses Unix domain sockets within a private directory to connect SMB clients to RPC services such as SAMR, LSA, or SPOOLSS. The vulnerability stems from inadequate sanitization of client-supplied pipe names, which allows attackers to include directory traversal sequences (../) in the pipe name. This manipulation enables SMB clients to bypass the intended private directory restrictions and connect to arbitrary Unix domain sockets elsewhere on the system. Since these sockets often run with root privileges, an attacker can gain unauthorized access to sensitive services or cause service disruptions. The vulnerability requires no authentication or user interaction, making it remotely exploitable over the network. The CVSS 3.1 score of 9.1 reflects the critical impact on integrity and availability, with low attack complexity and no privileges required. While no public exploits are currently known, the vulnerability poses a significant risk due to Samba's widespread use in enterprise Linux environments and its role in critical system services. The flaw could be leveraged to compromise system components, escalate privileges, or cause denial of service conditions.

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 27 Nov 2025, 20:27 UTC

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