#VU16159 Security restrictions bypass in Samba - CVE-2018-16857

Vulnerability identifier: #VU16159

Vulnerability risk: Low

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-16857

CWE-ID: CWE-264

Exploitation vector: Network

Exploit availability: No

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

Vendor: Samba

Description

The vulnerability allows a remote attacker to bypass security restrictions.

The vulnerability exists due to AD DC configurations watching for bad passwords (to restrict brute forcing of passwords) in a window of more than 3 minutes may not watch for bad passwords at all. A remote attacker can bypass security restrictions and modify arbitrary data.

Mitigation
Update to version 4.9.3.

Vulnerable software versions

Samba: 4.9.0 - 4.9.1

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External links
https://www.samba.org/samba/security/CVE-2018-16857.html

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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