Cyber Resilience

CVE-2023-21727

High

Published: 11 April 2023

Published
11 April 2023
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.1104 93.6th percentile
Risk Priority 24 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-21727 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Windows Server 2008. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 6.4% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis

CVE-2023-21727 is a remote code execution vulnerability in the Remote Procedure Call Runtime component of Windows. It carries a CVSS 3.1 score of 8.8 and is associated with CWE-122, indicating a heap-based buffer overflow that can be triggered remotely.

An authenticated attacker with network access and low privileges can exploit the flaw without user interaction to achieve arbitrary code execution with the privileges of the affected process, resulting in full compromise of confidentiality, integrity, and availability on the target system.

Microsoft’s security advisory for CVE-2023-21727 directs administrators to apply the updates released in the April 2023 Patch Tuesday cycle; the guidance emphasizes installing the vendor patches as the primary mitigation, with no workarounds listed.

The EPSS score has remained essentially flat near 0.11, indicating moderate but stable exploitation interest since disclosure.

EU & UK References

Vulnerability details

Remote Procedure Call Runtime Remote Code Execution Vulnerability

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

microsoft
windows 10 1607
≤ 10.0.14393.5850
microsoft
windows 10 1809
≤ 10.0.17763.4252
microsoft
windows 10 20h2
≤ 10.0.19042.2846
microsoft
windows 10 21h2
≤ 10.0.19044.2846
microsoft
windows 10 22h2
≤ 10.0.19045.2846
microsoft
windows 11 21h2
≤ 10.0.22000.1817
microsoft
windows 11 22h2
≤ 10.0.22621.1555
microsoft
windows server 2008
all versions, r2
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
all versions
+2 more product configuration(s) — see NVD for full list

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References