Vulnerability identifier: #VU59345

Vulnerability risk: Low

CVSSv3.1: 2.3 [CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2021-43566

CWE-ID: CWE-59

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Samba
Server applications / Directory software, identity management

Vendor: Samba

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.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Samba: 4.13.0 - 4.13.15

---

External links
http://www.samba.org/samba/security/CVE-2021-43566.html

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.