Main Vulnerability Database Vulnerabilities #VU70925

Use-after-free in Microsoft Windows and Windows Server - CVE-2023-21556

Published: January 10, 2023

Vulnerability identifier: #VU70925

CSH Severity: High

CVSS v4: 9.2 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2023-21556

CWE-ID: CWE-416

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error in Windows Layer 2 Tunneling Protocol (L2TP) implementation. A remote attacker can send specially crafted packets to the RAS server, trigger a use-after-free error and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of the vulnerable system.

Affected software

Microsoft Windows
Windows Server

How to mitigate CVE-2023-21556

Install updates from vendor's website.

External References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2023-21543

Related Security Bulletins