Raw vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:HSummary
CVE-2026-20853 is a high-severity Race Condition (CWE-362) vulnerability in Microsoft Windows 10 1607. Its CVSS base score is 7.4 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 25th 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-39 (Process Isolation) and SC-4 (Information in Shared System Resources) — see the control section below for these in your framework.
Deeper analysis AI-assisted summary
Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.
CVE-2026-20853 is a race condition vulnerability (CWE-362) affecting the Windows WalletService, published on 2026-01-13T18:16:13.990. The flaw arises from concurrent execution using a shared resource with improper synchronization, enabling an unauthorized attacker to elevate privileges locally. It carries a CVSS v3.1 base score of 7.4 (AV:L/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H).
A local attacker with no required privileges can exploit this race condition to achieve privilege escalation. The attack requires local access and high complexity due to the need for precise timing in concurrent operations, with no user interaction needed. Successful exploitation results in high impacts on confidentiality, integrity, and availability.
Microsoft's update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-20853 provides details on mitigation and patching for this vulnerability.
OWASP Top 10 for Web (2025)
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-2165
Vulnerability Data
Concurrent execution using shared resource with improper synchronization ('race condition') in Windows WalletService allows an unauthorized attacker to elevate privileges locally.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise Techniques
CVEs Like This One
Affected Assets
Mitigating Controls
Control response
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Mitigating Controls (NIST 800-53 r5) AI
Maintaining separate execution domains for each process structurally eliminates unintended concurrent access to the same shared resources.
Preventing unintended information transfer through shared system resources directly addresses the improper concurrent modification that defines a race 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.
Secure SDLC practices directly require proper synchronization primitives and concurrency testing that prevent race conditions.
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.
Security testing can detect race conditions, but does not prevent them at design or coding time.
Secure SDLC mandates concurrency controls and synchronization primitives that directly prevent race conditions.
Application security requirements can specify thread-safety and locking rules, but do not prescribe implementation details.
Secure architecture principles require proper synchronization and resource isolation, addressing the root cause of CWE-362.
Secure coding standards explicitly forbid unsafe concurrent access patterns and mandate atomic operations or locks.
Change management reduces introduction of concurrency bugs during updates, yet does not address the weakness itself.