CVEs / CVE-2020-0601
CVE-2020-0601: Microsoft Windows CryptoAPI Spoofing Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- high 8.1 CVSS 3.1 (NVD)
- EPSS 89% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
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.
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 and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Microsoft Windows | 10 Version 1803 for 32-bit Systems | — |
| Microsoft Windows | 10 Version 1803 for x64-based Systems | — |
| Microsoft Windows | 10 Version 1803 for ARM64-based Systems | — |
| Microsoft Windows | 10 Version 1809 for 32-bit Systems | — |
| Microsoft Windows | 10 Version 1809 for x64-based Systems | — |
| Microsoft Windows | 10 Version 1809 for ARM64-based Systems | — |
| Microsoft Windows | 10 Version 1709 for 32-bit Systems | — |
| Microsoft Windows | 10 Version 1709 for x64-based Systems | — |
| Microsoft Windows | 10 Version 1709 for ARM64-based Systems | — |
| Microsoft Windows | 10 for 32-bit Systems | — |
| Microsoft Windows | 10 for x64-based Systems | — |
| Microsoft Windows | 10 Version 1607 for 32-bit Systems | — |
| Microsoft Windows | 10 Version 1607 for x64-based Systems | — |
| Microsoft Windows Server | version 1803 (Core Installation) | — |
| Microsoft Windows Server | 2019 | — |
| Microsoft Windows Server | 2019 (Core installation) | — |
| Microsoft Windows Server | 2016 | — |
| Microsoft Windows Server | 2016 (Core installation) | — |
| Microsoft Windows 10 Version 1903 for 32-bit Systems | unspecified | — |
| Microsoft Windows 10 Version 1903 for x64-based Systems | unspecified | — |
| Microsoft Windows 10 Version 1903 for ARM64-based Systems | unspecified | — |
| Microsoft Windows Server, version 1903 (Server Core installation) | unspecified | — |
| Microsoft Windows 10 Version 1909 for 32-bit Systems | unspecified | — |
| Microsoft Windows 10 Version 1909 for x64-based Systems | unspecified | — |
| Microsoft Windows Server, version 1909 (Server Core installation) | unspecified | — |
| Microsoft Windows 10 Version 1909 for ARM64-based Systems | unspecified | — |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 3 May 2022 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 8.1 highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:NScored by NVD |
|---|---|
| Weakness | CWE-295 |
References
- CVE-2020-0601 on NVD
- CVE-2020-0601 in the CISA KEV catalog
- https://www.cisa.gov/news-events/directives/ed-20-02-mitigate-windows-vulnerabilities-january-2020-patch-tuesday (cited by CISA)
- CVE-2020-0601 on OSV
- http://packetstormsecurity.com/files/155960/CurveBall-Microsoft-Windows-CryptoAPI-Spoofing-Proof-Of-Concept.html Third Party Advisory, VDB Entry
- http://packetstormsecurity.com/files/155961/CurveBall-Microsoft-Windows-CryptoAPI-Spoofing-Proof-Of-Concept.html Third Party Advisory, VDB Entry
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0601 Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-0601 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.