CVE-2020-0601: Microsoft Windows CryptoAPI Spoofing Vulnerability
- Is it exploited?
Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 3 Nov 2021, 659 days after the CVE record was published.
- How likely is exploitation in the next 30 days?
- 89.1%
EPSS score, percentile 99.8 of all scored records
- How severe?
- 8.1 High
CVSS v3.1 base score, from CISA's enrichment of the record
- What should I do?
CISA deadline 3 May 2022. Apply updates per vendor instructions.
The CVE record links no vendor advisory, patch or mitigation.
- Which versions are affected?
Affected
- 10 Version 1803 for 32-bit Systems
- 10 Version 1803 for x64-based Systems
- 10 Version 1803 for ARM64-based Systems
- 10 Version 1809 for 32-bit Systems
- 10 Version 1809 for x64-based Systems
- 10 Version 1809 for ARM64-based Systems
and 19 more in the table below
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
What to do
Required action, set by CISA
Apply updates per vendor instructions.
CISA due date for this action: 3 May 2022.
Advisories and patches
The CVE record links no vendor advisory, patch or mitigation.
Linked from CISA's catalog entry
- https://www.cisa.gov/news-events/directives/ed-20-02-mitigate-windows-vulnerabilities-january-2020-patch-tuesday
- https://nvd.nist.gov/vuln/detail/CVE-2020-0601
Affected products and versions
As listed in the CVE record.
| Status | Versions |
|---|---|
| Affected | 10 Version 1803 for 32-bit Systems |
| Affected | 10 Version 1803 for x64-based Systems |
| Affected | 10 Version 1803 for ARM64-based Systems |
| Affected | 10 Version 1809 for 32-bit Systems |
| Affected | 10 Version 1809 for x64-based Systems |
| Affected | 10 Version 1809 for ARM64-based Systems |
| Affected | 10 Version 1709 for 32-bit Systems |
| Affected | 10 Version 1709 for x64-based Systems |
| Affected | 10 Version 1709 for ARM64-based Systems |
| Affected | 10 for 32-bit Systems |
| Affected | 10 for x64-based Systems |
| Affected | 10 Version 1607 for 32-bit Systems |
And 1 more version entries in the CVE record.
| Status | Versions |
|---|---|
| Affected | version 1803 (Core Installation) |
| Affected | 2019 |
| Affected | 2019 (Core installation) |
| Affected | 2016 |
| Affected | 2016 (Core installation) |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
| Status | Versions |
|---|---|
| Affected | unspecified |
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
About this vulnerability
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.
Summary: CISA's KEV catalog, as of 28 Oct 2026.
- CISA added CVE-2020-0601 to its Known Exploited Vulnerabilities (KEV) catalog on 3 Nov 2021.
- CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
- The due date CISA sets for the required action is 3 May 2022.
- The CVE record was published on 14 Jan 2020, 659 days before it was added to KEV.
- The CVE record carries a CVSS v3.1 base score of 8.1 (High), taken from CISA's enrichment of the record.
- FIRST's EPSS model puts the probability of exploitation in the next 30 days at 89.1% (percentile 99.8), as of 28 Oct 2026.
- CISA's SSVC assessment in the CVE record: exploitation active, automatable no, technical impact total.
Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.
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'.
Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.
Weakness
- CWE-295: Improper Certificate Validation
CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.
Timeline
| Date | Event |
|---|---|
| 14 Jan 2020 | CVE record published |
| 3 Nov 2021 | Added to CISA KEV |
| 3 May 2022 | CISA due date for the required action |
| 21 Oct 2025 | CVE record last updated |
References
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