Link following in Samba - CVE-2021-43566
Published: January 10, 2022
Vulnerability identifier: #VU59345
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:A/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2021-43566
CWE-ID: CWE-59
Exploitation vector: Adjecent network
Exploit availability:
No public exploit available
Vendor: Samba
Affected software:
Samba
Samba
Detailed vulnerability description
The vulnerability allows a remote user to bypass implemented security restrictions.
The vulnerability exists due to a symlink race condition when creating directories. A remote authenticated user can use SMB1 or NFS symlink race to create directories on the Unix filesystem outside of the share definition.
Successful exploitation of the vulnerability requites that the user has permissions to create folder in the target directory.
How to mitigate CVE-2021-43566
Install updates from vendor's website.