Cyber Resilience

CVE-2026-50439

Memory Safety in Microsoft Windows 10 21H2 ≤ 10.0.19044.7548

Published
14 July 2026
Modified
22 July 2026
Patch / advisory
CVSS Score v3.1 8.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0053 42th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-50439 is a high-severity Use After Free (CWE-416) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 8.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 42th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SC-7 (Boundary Protection) and SI-16 (Memory Protection) — see the control section below for these in your framework.

EU & UK References

Vulnerability Data

Use after free in Microsoft Message Queuing Queue Manager allows an unauthorized attacker to execute code over a network.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
Why these techniques?

Remote code execution vulnerability in a network-accessible service (MSMQ) directly enables exploitation of public-facing or remote applications for initial access.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-50694Same product: Microsoft Windows 10 1607
CVE-2026-54995Same product: Microsoft Windows 10 1607
CVE-2026-45599Same product: Microsoft Windows 10 1607
CVE-2026-50312Same product: Microsoft Windows 10 1607
CVE-2026-50500Same product: Microsoft Windows 10 1607
CVE-2026-50505Same product: Microsoft Windows 10 1607
CVE-2026-50474Same product: Microsoft Windows 10 1607
CVE-2026-50359Same product: Microsoft Windows 10 1607
CVE-2026-50476Same product: Microsoft Windows 10 1607
CVE-2026-54128Same product: Microsoft Windows 10 1607

Affected Assets

microsoft
windows 10 1607
≤ 10.0.14393.9339 · ≤ 10.0.14393.9339
microsoft
windows 10 1809
≤ 10.0.17763.9020 · ≤ 10.0.17763.9020
microsoft
windows 10 21h2
≤ 10.0.19044.7548 · ≤ 10.0.19044.7548 · ≤ 10.0.19044.7548
microsoft
windows 10 22h2
≤ 10.0.19045.7548 · ≤ 10.0.19045.7548 · ≤ 10.0.19045.7548
microsoft
windows 11 24h2
≤ 10.0.26100.8875 · ≤ 10.0.26100.8875
microsoft
windows 11 25h2
≤ 10.0.26200.8875 · ≤ 10.0.26200.8875
microsoft
windows 11 26h1
≤ 10.0.28000.2269 · ≤ 10.0.28000.2525
microsoft
windows server 2012
all versions, r2
microsoft
windows server 2016
≤ 10.0.14393.9339
microsoft
windows server 2019
≤ 10.0.17763.9020
+2 more product configuration(s) — see NVD for full list

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • SI-16 Memory Protection
  • SC-7 Boundary Protection
  • SI-10 Information Input Validation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 3 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V1.4.3

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly implements memory protections that block use-after-free exploitation leading to code execution in the Queue Manager.

prevent

Boundary protection restricts network access to the vulnerable MSMQ service, preventing remote unauthenticated exploitation.

prevent

Input validation on MSMQ messages can block malformed requests that trigger the use-after-free condition.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly incorporate memory-safety tooling and reviews that prevent most use-after-free defects.

ID.RA-01 partial match
prevents

Vulnerability identification processes can discover use-after-free issues via scanning or analysis but do not prevent their introduction.

PR.PS-02 partial match
prevents

Routine patching removes known use-after-free instances after they have been introduced in released software.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

detects

Security testing in development can detect use-after-free bugs before release.

prevents

Secure SDLC mandates memory-safety practices that reduce use-after-free defects.

prevents

Application security requirements can specify memory-management rules that mitigate use-after-free.

prevents

Secure architecture principles include memory-safety design choices that limit use-after-free exposure.

prevents

Secure coding standards directly prescribe avoidance of use-after-free patterns.

prevents

Change-management processes help ensure memory-safety fixes are deployed consistently.

References