Cyber Posture

CVE-2026-23665

High

Published: 10 March 2026

Published
10 March 2026
Modified
20 March 2026
KEV Added
Patch
CVSS Score 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0003 8.7th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-23665 is a high-severity Heap-based Buffer Overflow (CWE-122) vulnerability in Microsoft Linux Diagnostic Extension. Its CVSS base score is 7.8 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 8.7th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-16 (Memory Protection) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploitation for Privilege Escalation (T1068). What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly requires timely remediation of flaws like this heap-based buffer overflow through patching as referenced in Microsoft's update guide.

prevent

Implements memory protection safeguards such as ASLR and DEP to prevent exploitation of heap buffer overflows for privilege escalation.

prevent

Enforces least privilege to limit the initial access and potential impact of local low-privilege attackers exploiting the vulnerability.

MITRE ATT&CK Enterprise TechniquesAI

T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
Why these techniques?

Heap buffer overflow in Azure Linux VM directly enables local privilege escalation by a low-privileged attacker.

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Heap-based buffer overflow in Azure Linux Virtual Machines allows an authorized attacker to elevate privileges locally.

Deeper analysisAI

CVE-2026-23665 is a heap-based buffer overflow vulnerability, associated with CWE-122 and CWE-787, affecting Azure Linux Virtual Machines. Published on 2026-03-10, it carries a CVSS v3.1 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact with relatively low barriers to exploitation.

The vulnerability enables a local authorized attacker with low privileges to exploit the heap-based buffer overflow, achieving privilege escalation on the affected Azure Linux Virtual Machine. Exploitation requires local access and low attack complexity, with no user interaction needed, potentially granting the attacker high-level confidentiality, integrity, and availability impacts.

Microsoft's update guide provides details on mitigation and patching for CVE-2026-23665, available at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-23665. Security practitioners should consult this resource for specific remediation steps.

Details

CWE(s)

Affected Products

microsoft
linux diagnostic extension
1.0.0 — 2.1.24

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References