Vulnerability identifier: #VU293

Vulnerability risk: Medium

CVSSv3.1: 5 [CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L/E:P/RL:O/RC:C]

CVE-ID: CVE-2016-3237

CWE-ID: CWE-255

Exploitation vector: Local network

Exploit availability: Yes

Vulnerable software:
Windows
Operating systems & Components / Operating system
Windows Server
Operating systems & Components / Operating system

Vendor: Microsoft

Description

The vulnerability allows an attacker with access to local network to gain elevated privileges.

The vulnerability exists in Kerberos implementation when handling password change request. A local attacker can make the operating system to fall back to NT LAN Manager (NTLM) Authentication Protocol as the default authentication protocol.

Successful exploitation of this vulnerability will allow a local attacker to launch a man-in-the-middle (MiTM) attack against the traffic passing between a domain controller and the target machine, intercept and decrypt credentials during password change request.

Vulnerable software versions

Windows: Vista, 7, 8.1 - 8.1 RT, 10

Windows Server: 2008 - 2012 R2

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External links
http://technet.microsoft.com/en-us/library/security/ms16-101.aspx

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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. However, proof of concept for this vulnerability is available.