ACTIVELY EXPLOITED

CVE-2020-0601: Microsoft Windows CryptoAPI Spoofing Vulnerability

Facts
VendorMicrosoft
ProductWindows
Actively exploitedYes
Added to CISA KEV3 Nov 2021
CISA federal deadline3 May 2022
Weakness (CWE)CWE-295

Required action (CISA's text)

Apply updates per vendor instructions.

Description (NVD)

Microsoft Windows CryptoAPI (Crypt32.dll) contains a spoofing vulnerability in the way it 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. A successful exploit could also allow the attacker to conduct man-in-the-middle attacks and decrypt confidential information on user connections to the affected software. The vulnerability is also known under the moniker of CurveBall.

SOURCES

Other Microsoft flaws

Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.