PT-2023-1046 · Microsoft · Windows

Yuki Chen · Published 2023-01-10 · Updated 2024-05-29 · CVE-2023-21556

Positive Technologies (AI Summary)

CVSS v3.1

8.1

High

Base vector

AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Windows versions prior to the fixed version

Description The issue is related to the implementation of the Layer 2 Tunneling Protocol (L2TP) in Microsoft Windows, specifically involving the use of memory after it has been freed. This can be exploited by a remote attacker who sends a specially crafted connection request to a RAS server, potentially allowing the execution of arbitrary code.

Recommendations For Windows versions prior to the fixed version, apply the necessary patch or update to resolve the issue. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

RCE

Integer Underflow

Use After Free

Weakness Enumeration

CWE-191

CWE-416

Related Identifiers

BDU:2023-00140

CVE-2023-21556

Affected Products

Windows

References · 14

• https://nvd.nist.gov/vuln/detail/CVE-2023-21556 · Security Note
• https://safe-surf.ru/specialists/bulletins-nkcki/688435 · Security Note
• https://msrc.microsoft.com/update-guide/en-US/advisory/CVE-2023-21556 · Vendor Advisory
• https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2023-21556 · Vendor Advisory
• https://safe-surf.ru/specialists/bulletins-nkcki/688799 · Security Note
• https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-21556 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2023-21556 · Vendor Advisory
• https://bdu.fstec.ru/vul/2023-00140 · Security Note
• http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-21556 · Security Note
• https://t.me/cvenotify/41760 · Telegram Post
• https://t.me/cibsecurity/56308 · Telegram Post
• https://t.me/cvenotify/41761 · Telegram Post
• https://t.me/cvenotify/42247 · Telegram Post
• https://t.me/cibsecurity/56292 · Telegram Post