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Full vulnerability report · 2020
CVE-2020-0601High confidence

Microsoft Windows CryptoAPI Spoofing Vulnerability

Microsoft · Windows

8.1HighCVSS 3.1
Recommended action
Patch now

CISA confirms exploitation in the wild and lists 2022-05-03 as the remediation due date.

Patch available
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

1 current
SEVD-2021-285-05 · CSAF 2.0 · revision 1.0.0 · finalSchneider Electric CPCERTConext™ Advisor & Conext™ Control V2
3 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • Schneider Electric Conext™ Advisor 2 Cloud 2.02 and below
  • Schneider Electric Conext™ Advisor 2 Gateway 1.28.45 and below
  • Schneider Electric Conext™ Control V2 Gateway 2.6 and below
Summary
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'.
Remediation
Version Windows 10 of the Microsoft Windows includes a fix for this vulnerability and is available for download here: • https://www.microsoft.com/en-in/software-download/windows10 • Reboot is required
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2020-2099

CISA KEV mirrored by ENISA

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'.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 3 Nov 2021. Evidence sources: cisa_kev.
ENISA score
8.1 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionPatch now

CISA confirms exploitation in the wild and lists 2022-05-03 as the remediation due date.

Patch available
01

What, why and how

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.

What

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.

Why

The product does not validate, or incorrectly validates, a certificate.

How

An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

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.

Why

The product does not validate, or incorrectly validates, a certificate.

How

An attacker operating through a network path may attempt exploitation without authentication after a user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2021-11-03.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Improper Certificate Validation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Required interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-295 ↗

CWE-295: Improper Certificate Validation. The product does not validate, or incorrectly validates, a certificate.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-295CISA KEV
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2020-2099Known-exploited evidence recorded

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'.

Official EUVD record
CERT-FR · French · CERTFR-2021-AVI-772Multiples vulnérabilités dans les produits Schneider

Schneider SEVD-2021-285-05 du 12 octobre 2021 https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-285-05 Bulletin de sécurité Schneider SEVD-2021-285-06 du 12 octobre 2021 https://download.schneider-electric.com/files?p_Doc_Ref=SEVD-2021-285-06 Référence CVE CVE-2019-0685 https://www.cve.org/CVERecord?id=CVE-2019-0685 Référence CVE CVE-2019-0803 https://www.cve.org/CVERecord?id=CVE-2019-0803 Référence CVE CVE-2019-0859 https://www.cve.org/CVERecord?id=CVE-2019-0859 Référence CVE CVE-2019-1040 https://www.cve.org/CVERecord?id=CVE-2019-1040 Référence CVE CVE-2019-11135 https://www.cve.org/CVERecord?id=CVE-2019-11135 Référence CVE CVE-2020-0601 https://www.cve.org/CVERecord?id=CVE-2020-0601 Référence CVE CVE-2020-0609 https://www.cve.org/CVERecord?id=CVE-2020-0609 Référence CVE CVE-2020-0610 https://www.cve.org/CVERecord?id=CVE-2020-0610 Référence CVE CVE-2020-0796 https://www.cve.org/CVERecord?id=CVE-2020-0796 Référence CVE CVE-2020-0938 https://www.cve.org/CVERecord?id=CVE-2020-0938 Référence CVE CVE-2020-1020 https://www.cve.org/CVERecord?id=CVE-2020-1020 Référence CVE CVE-2020-1350 https://www.cve.org/CVERecord?id=CVE-2020-1350 Référence CVE CVE-2020-13987 https://www.cve.org/CVERecord?id=CVE-2020-13987 Référence CVE CVE-2020-1472 https://www.cve.org/CVERecord?id=CVE-2020-1472

Official advisory
CERT-FR · French · CERTFR-2020-AVI-043Multiples vulnérabilités dans Google Chrome

De multiples vulnérabilités ont été découvertes dans Google Chrome. Elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur.

Official advisory
CERT-FR · French · CERTFR-2020-AVI-026Multiples vulnérabilités dans Microsoft Windows

n 1903 (Server Core installation) Windows Server, version 1909 (Server Core installation) Résumé De multiples vulnérabilités ont été corrigées dans Microsoft Windows . Elles permettent à un attaquant de provoquer une exécution de code à distance, une atteinte à la confidentialité des données, une élévation de privilèges, un contournement de la fonctionnalité de sécurité et un déni de service. Solution Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation). Documentation Bulletin de sécurité Microsoft du 14 janvier 2020 https://portal.msrc.microsoft.com/fr-FR/security-guidance Référence CVE CVE-2020-0601 https://www.cve.org/CVERecord?id=CVE-2020-0601 Référence CVE CVE-2020-0607 https://www.cve.org/CVERecord?id=CVE-2020-0607 Référence CVE CVE-2020-0608 https://www.cve.org/CVERecord?id=CVE-2020-0608 Référence CVE CVE-2020-0609 https://www.cve.org/CVERecord?id=CVE-2020-0609 Référence CVE CVE-2020-0610 https://www.cve.org/CVERecord?id=CVE-2020-0610 Référence CVE CVE-2020-0611 https://www.cve.org/CVERecord?id=CVE-2020-0611 Référence CVE CVE-2020-0612 https://www.cve.org/CVERecord?id=CVE-2020-0612 Référence CVE CVE-2020-0613 https://www.cve.org/CVERecord?id=CVE-2020-0613 Référence CVE CVE-2020-0614 https://www.cve.org/CVERecord?id=CVE-2020-0614 Ré

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Schneider Electric Conext™ Advisor 2 Cloud 2.02 and below; Schneider Electric Conext™ Advisor 2 Gateway 1.28.45 and below; Schneider Electric Conext™ Control V2 Gateway 2.6 and below
Fixed
Schneider Electric Microsoft Windows 10
Action
Version Windows 10 of the Microsoft Windows includes a fix for this vulnerability and is available for download here: • https://www.microsoft.com/en-in/software-download/windows10 • Reboot is required
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 14 Jan 2020 · Last source change 21 Oct 2025, 23:35 UTC · CWE-295 · Improper Certificate Validation

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2020-2099
Product sourceVendor CSAF · Schneider Electric CPCERT
Remediation sourceVendor CSAF · Schneider Electric CPCERT
CWE sourceCISA ADP
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2020-2099↗Vendor CSAF · Schneider Electric CPCERT↗CISA KEV record↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2020-0601 · cve.blacktree.nl