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MSRC compact vulnerability detail

CVE-2026-40377 · Microsoft Cryptographic Services Elevation of Privilege Vulnerability

Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.

Severity
Important
Impact
Elevation of Privilege
CVSS
7.8 base · 6.8 temporal
Release
2026-05-12
Signals
Windows Cryptographic Services Elevation of Privilege Exploited: No Publicly disclosed: No Exploitability: Exploitation Less Likely
CWE
CWE-122: Heap-based Buffer Overflow
Patch Diff
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Description
Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.
FAQ / Articles
Windows Cryptographic Services Elevation of Privilege Vulnerability
Heap-based buffer overflow in Windows Cryptographic Services allows an authorized attacker to elevate privileges locally.
FAQ
What privileges could be gained by an attacker who successfully exploited this vulnerability? An attacker who successfully exploited this vulnerability could gain SYSTEM privileges.