Samba up to 4.17.11/4.18.7/4.19.0 AD DC Busy RPC denial of service

Summaryinfo

A vulnerability was found in Samba up to 4.17.11/4.18.7/4.19.0. It has been rated as problematic. This affects an unknown part of the component AD DC Busy RPC Handler. This manipulation causes denial of service. The identification of this vulnerability is CVE-2023-42670. It is possible to initiate the attack remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Samba up to 4.17.11/4.18.7/4.19.0 (File Transfer Software) and classified as problematic. Affected by this vulnerability is an unknown function of the component AD DC Busy RPC Handler. The manipulation with an unknown input leads to a denial of service vulnerability. The CWE definition for the vulnerability is CWE-404. The product does not release or incorrectly releases a resource before it is made available for re-use. As an impact it is known to affect availability. The summary by CVE is:

A flaw was found in Samba. It is susceptible to a vulnerability where multiple incompatible RPC listeners can be initiated, causing disruptions in the AD DC service. When Samba's RPC server experiences a high load or unresponsiveness, servers intended for non-AD DC purposes (for example, NT4-emulation "classic DCs") can erroneously start and compete for the same unix domain sockets. This issue leads to partial query responses from the AD DC, causing issues such as "The procedure number is out of range" when using tools like Active Directory Users. This flaw allows an attacker to disrupt AD DC services.

The weakness was shared 10/11/2023. The advisory is shared at bugzilla.samba.org. This vulnerability is known as CVE-2023-42670 since 09/13/2023. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1499 for this issue.

The vulnerability scanner Nessus provides a plugin with the ID 239932 (TencentOS Server 4: samba (TSSA-2025:0014)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.17.12, 4.18.8 or 4.19.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (239932). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• File Transfer Software

Name

• Samba

Version

• 4.0
• 4.1
• 4.2
• 4.3
• 4.4
• 4.5
• 4.6
• 4.7
• 4.8
• 4.9
• 4.10
• 4.11
• 4.12
• 4.13
• 4.14
• 4.15
• 4.16
• 4.17
• 4.17.0
• 4.17.1
• 4.17.2
• 4.17.3
• 4.17.4
• 4.17.5
• 4.17.6
• 4.17.7
• 4.17.8
• 4.17.9
• 4.17.10
• 4.17.11
• 4.18
• 4.18.0
• 4.18.1
• 4.18.2
• 4.18.3
• 4.18.4
• 4.18.5
• 4.18.6
• 4.18.7
• 4.19.0

License

• open-source

Website

• Product: https://www.samba.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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