CISA KEV catalog
Confirmed active exploitation.
Listed in CISA's catalog of Known Exploited Vulnerabilities: attackers are using it in real attacks. Patch it with priority.
- Name
- Microsoft Windows CryptoAPI Spoofing Vulnerability
- Added to catalog
- Remediation due date (US federal)
- Required action
- Apply updates per vendor instructions.
Description
A spoofing vulnerability exists in the way Windows CryptoAPI (Crypt32.dll) validates Elliptic Curve Cryptography (ECC) certificates.An attacker could exploit the vulnerability by using a spoofed code-signing certificate to sign a malicious executable, making it appear the file was from a trusted, legitimate source, aka 'Windows CryptoAPI Spoofing Vulnerability'.
Affected products
microsoft: windows 10 1507; microsoft: windows 10 1607; microsoft: windows 10 1709; microsoft: windows 10 1803; microsoft: windows 10 1809; microsoft: windows 10 1903; microsoft: windows 10 1909; microsoft: windows server 1803; microsoft: windows server 1903; microsoft: windows server 1909; microsoft: windows server 2016; microsoft: windows server 2019; golang: go; microsoft: windows
References7
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… PatchVendor Advisory
- portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-… PatchVendor Advisory
- packetstormsecurity.com/files/155960/CurveBall-Microsoft-Window… Third Party AdvisoryVDB Entry
- packetstormsecurity.com/files/155961/CurveBall-Microsoft-Window… Third Party AdvisoryVDB Entry
- packetstormsecurity.com/files/155960/CurveBall-Microsoft-Window… Third Party AdvisoryVDB Entry
- packetstormsecurity.com/files/155961/CurveBall-Microsoft-Window… Third Party AdvisoryVDB Entry
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=… US Government Resource
Metrics
- CVSS 3.1
-
8.1
HIGH
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N - EPSS — exploit probability
- 89% percentile: 100 · as of 10 November 2026
- CWE
- CWE-295
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