Privilege escalation in Microsoft Windows

1) NULL pointer dereference

EUVDB-ID: #VU17930

Risk: Medium

CVSSv3.1: 8.4 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C]

CVE-ID: CVE-2019-0808

CWE-ID: CWE-476 - NULL Pointer Dereference

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a NULL pointer dereference error in the win32k!MNGetpItemFromIndex when NtUserMNDragOver() system call within the win32k.sys kernel driver. A local user can use a specially crafted application to escape sandbox and execute arbitrary code on the target system with SYSTEM privileges.

Note, this vulnerability is being actively exploited in the wild along with vulnerability in Google Chrome described in (SB2019030405).

Mitigation

Install updates from vendor's website.

Vulnerable software versions

Windows: 7

Windows Server: 2008 - 2008 R2 SP1

External links

http://security.googleblog.com/2019/03/disclosing-vulnerabilities-to-protect.html
http://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0808

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.