CVE-2026-33827
Published: 14 April 2026
Summary
CVE-2026-33827 is a high-severity Race Condition (CWE-362) vulnerability in Microsoft Windows 10 21H2. Its CVSS base score is 8.1 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation of Remote Services (T1210); ranked in the top 47.0% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SI-2 (Flaw Remediation) and SC-4 (Information in Shared System Resources).
Deeper analysis
CVE-2026-33827 is a race condition vulnerability (CWE-362) in the Windows TCP/IP stack, stemming from concurrent execution using a shared resource with improper synchronization. This flaw allows an unauthorized attacker to execute arbitrary code over a network. The vulnerability carries a CVSS v3.1 base score of 8.1 (AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating high severity due to its potential for significant impact.
The vulnerability can be exploited by an unauthorized attacker with network access, requiring no privileges or user interaction but involving high attack complexity. Successful exploitation enables remote code execution, compromising confidentiality, integrity, and availability with high impact across affected systems.
Mitigation details are available in the Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-33827.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-22647
Vulnerability details
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows TCP/IP allows an unauthorized attacker to execute code over a network.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Race condition in Windows TCP/IP stack enables remote arbitrary code execution over the network with no authentication, directly mapping to exploitation of remote services for initial access.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly mitigates the race condition vulnerability by requiring identification, reporting, and timely correction of flaws in the Windows TCP/IP stack.
Prevents unauthorized information transfer via shared system resources, addressing the improper synchronization in concurrent TCP/IP execution.
Implements memory protection safeguards that mitigate arbitrary code execution resulting from the TCP/IP race condition exploitation.