CVE-2023-42670 Samba: ad dc busy rpc multiple listener dos
An attacker can disrupt Active Directory Domain Controller services by triggering incompatible RPC listeners, causing service unresponsiveness and partial query failures.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-42670?
CVE-2023-42670 is a medium-severity denial of service vulnerability in Fedoraproject Fedora, published on 3 Nov 2023. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
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.
Weakness: CWE-400
Which versions are affected by CVE-2023-42670?
It affects 2 products.
Products include Fedoraproject Fedora, Samba Samba.
How do I fix CVE-2023-42670?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2023-42670 being exploited?
There is no known exploitation of CVE-2023-42670 in the wild and no public exploit code.
Other vulnerabilities in Fedoraproject Fedora
Sources
Also known as ALPINE-CVE-2023-42670, AZL-31901, AZL-37028, DEBIAN-CVE-2023-42670, ECHO-9e4d-e76a-7140, GHSA-5qvm-gfmw-9v64 and 1 more.