CVE-2021-43566

Name of the Vulnerable Software and Affected Versions Samba versions prior to 4.13.16

Description The issue allows a malicious client to create a directory in an area of the server file system not exported under the share definition by using an SMB1 or NFS race. This can happen if SMB1 is enabled or the share is also available via NFS. The vulnerability is related to the unix extensions of SMB1 and NFS in the Samba package, which is caused by incorrect synchronization during concurrent execution.

Recommendations For versions prior to 4.13.16, update to version 4.13.16 or later to resolve the issue. As a temporary workaround, consider disabling SMB1 or restricting access to NFS shares to minimize the risk of exploitation. Avoid using SMB1 or NFS for sensitive data until the issue is resolved.