CVE Intelligence
CISA KEV High Cryptography

CVE-2020-0601 — Microsoft Windows CryptoAPI Spoofing Vulnerability

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'.

Published Jan 14, 2020 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: microsoft

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (exploitdb)+8
  • EPSS 89.4% (30-day exploitation probability)+15
  • Technical severity (high)+6

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Nov 3, 2021
EPSS FIRST
89.44%
ahead of 100% of scored CVEs · Oct 14, 2026
Affects
Golang
Go and 14 more
CVSS base
8.1
High · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

CISA required action CISA

Apply updates per vendor instructions.

US federal deadline: May 3, 2022 — passed 1626 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Golang Go, Microsoft Windows, Microsoft Windows 10 1507…).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. Apply the fixed version or the patch documented under Remediation.
  5. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  6. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
  7. Search available logs for exploit probes matching the vulnerability class (cryptography), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Golang Go ≥ 1.12 and < 1.12.16≥ 1.13 and < 1.13.7 Vulnerable NIST National Vulnerability Database
Microsoft Windows version 10 for 32-bit Systemsversion 10 Version 1709 for 32-bit Systemsversion 10 Version 1709 for x64-based Systemsversion 10 Version 1809 for ARM64-based Systemsversion 10 Version 1809 for x64-based Systemsversion 10 Version 1803 for 32-bit Systemsversion 10 Version 1803 for x64-based Systemsversion 10 Version 1709 for ARM64-based Systems
and 5 more version 10 for x64-based Systemsversion 10 Version 1607 for 32-bit Systemsversion 10 Version 1607 for x64-based Systemsversion 10 Version 1803 for ARM64-based Systemsversion 10 Version 1809 for 32-bit Systems
Vulnerable CVE Program (cve.org) e CISA ADP
Microsoft Windows 10 1507 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1607 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1709 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1803 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1809 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1903 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows 10 1909 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows Server version 2016version 2016 (Core installation)version version 1803 (Core Installation)version 2019version 2019 (Core installation) Vulnerable CVE Program (cve.org) e CISA ADP
Microsoft Windows Server 1803 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows Server 1903 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows Server 1909 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows Server 2016 versions not specified by the source Vulnerable NIST National Vulnerability Database
Microsoft Windows Server 2019 versions not specified by the source Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.1 CVSS 3.1 High 2.8 5.2 nvd@nist.gov via NIST National Vulnerability Database
8.1 CVSS 3.1 High 2.8 5.2 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
8.1 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.1 CVSS 3.1 High — — CISA-ADP via CVE Program (cve.org) e CISA ADP
5.8 CVSS 2.0 Medium 8.6 4.9 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-295 · Improper Certificate Validation

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Nov 3, 2021
Federal deadline
May 3, 2022
passed 1626 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 89.44%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Check TLS negotiations and unexpected certificates in the component’s traffic.
  • Hunt retroactively in logs from before Nov 3, 2021 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · microsoft/windows, microsoft/windows server
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • Affected products added · microsoft/windows 10 1507, microsoft/windows 10 1607, microsoft/windows 10 1709, microsoft/windows 10 1803, microsoft/wi
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 8.1
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2021
  • Added to CISA KEV catalog
    Nov 2, 2021 · CISA
  • 2020
  • CVE published
    Jan 14, 2020 · microsoft

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

Elsewhere on this site

Golang
every CVE for this vendor
2021-11
what else CISA listed that month
Cryptography
same class
CWE-295
other pages naming this weakness

Related CVEs (same products)

  • Medium CVE-2026-97844 Role: DNS Server Information Disclosure Vulnerability 2d
  • Medium CVE-2026-97842 Role: DNS Server Information Disclosure Vulnerability 2d
  • Medium CVE-2026-97839 Role: DNS Server Information Disclosure Vulnerability 2d
  • Medium CVE-2026-97840 Role: DNS Server Information Disclosure Vulnerability 2d
  • Medium CVE-2026-97841 Role: DNS Server Information Disclosure Vulnerability 2d
  • Medium CVE-2026-97843 Role: DNS Server Information Disclosure Vulnerability 2d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2020-0601 is "Microsoft Windows CryptoAPI Spoofing Vulnerability", rated High. It affects Go (Golang); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 8.1 describes technical severity. EPSS 89.44% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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