Published severityCritical→Operational priority:Critical, unchanged from published severity.unchanged
Evidence used
CISA confirms exploitation in the wild.
A structured source references public exploit or proof-of-concept material.
The selected CVSS metric records a network-reachable, unauthenticated path with no user interaction.
EPSS is 99.22% for the current model date.
Compensating controls
Validate the affected product branch and deploy the verified fixed release.
Restrict the affected network interface to trusted sources where business-safe.
Increase monitoring for the attack path and post-exploitation behaviour described in the report.
Verification
Confirm that the asset runs Microsoft .NET Framework and falls inside the recorded affected range.
Verify the installed build against the product-specific fixed version after deployment.
Validate exposure, authentication requirements and compensating controls in the actual environment.
Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Optional official sources
National CERT insights ?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.
Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.
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-2020-2140
CISA KEV mirrored by ENISA
A remote code execution vulnerability exists when the Microsoft .NET Framework fails to validate input properly, aka '.NET Framework Remote Code Execution Injection Vulnerability'.
EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 3 Nov 2021. Evidence sources: cisa_kev.
ENISA score
9.8 · 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 .NET Framework contains an improper input validation vulnerability that allows for remote code execution.
What
Microsoft .NET Framework contains an improper input validation vulnerability that allows for remote code execution.
Why
The product does not properly neutralize special elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.
What
Microsoft .NET Framework contains an improper input validation vulnerability that allows for remote code execution.
Why
The product does not properly neutralize special elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system.
How
An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may execute code or commands in the affected security context.
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.Reference recorded
A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.
Likely attack path
a network path → XML Injection (aka Blind XPath Injection) → execute code or commands in the affected security context
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
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-91: XML Injection (aka Blind XPath Injection). The product does not properly neutralize special elements that are used in XML, allowing attackers to modify the syntax, content, or commands of the XML before it is processed by an end system.
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:N/S:U/C:H/I:H/A:H
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.UINoneUser interaction: No action by another user is required.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.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
After compromise, an attacker may use built-in shells, scripting engines, scheduled tasks and native network utilities for discovery, persistence or movement. This is a plausible LoTL path, not evidence that it has occurred for every attack.
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2020-2140Known-exploited evidence recorded
A remote code execution vulnerability exists when the Microsoft .NET Framework fails to validate input properly, aka '.NET Framework Remote Code Execution Injection Vulnerability'.
Official EUVD record ↗CERT-FR · French · CERTFR-2020-AVI-027Multiples vulnérabilités dans Microsoft .Net
De multiples vulnérabilités ont été corrigées dans Microsoft .Net . Elles permettent à un attaquant de
provoquer une exécution de code à distance et un déni de service.
Official advisory ↗JVN iPedia · Japanese · JVNDB-2020-001080Microsoft .NET Framework におけるリモートでコードを実行される脆弱性
Microsoft .NET Framework には、入力の適切な検証に失敗した場合、リモートでコードを実行される脆弱性が存在します。 ベンダは、本脆弱性を「.NET Framework のコード挿入の脆弱性」として公開しています。
Official advisory ↗KISA KrCERT/CC · Korean · KNVD-5087MS 1월 보안 위협에 따른 정기 보안 업데이트 권고
34306, 4534310
##### □ 해결책
o 영향 받는 소프트웨어를 이용하는 경우 마이크로소프트사의 보안 패치 적용
5. Microsoft Office 관련 소프트웨어 보안 업데이트
##### □ 설명
o 공격자가 특수하게 제작된 악성 응용 프로그램을 실행할 경우, 원격코드실행을 허용하는 취약점
o 관련취약점 :
- 원격코드실행 취약점(CVE-2020-0647, CVE-2020-0650, CVE-2020-0651, CVE-2020-0652, CVE-2020-0653)
- 스푸핑 취약점(CVE-2020-0647)
o 영향 : 원격코드실행
o 중요도 : 중요
o 관련 KB번호
- 4528760, 4534251, 4534271, 4534273, 4534276, 4534283, 4534293, 4534297, 4534303, 4534306, 4534310
##### □ 해결책
o 영향 받는 소프트웨어를 이용하는 경우 마이크로소프트사의 보안 패치 적용
6. .NET Framework와 관련 소프트웨어 보안 업데이트
##### □ 설명
o 공격자가 특수하게 제작된 악성 응용 프로그램을 실행할 경우, 원격코드실행을 허용하는 취약점
o 관련취약점 :
- 원격코드실행 취약점(CVE-2020-0603, CVE-2020-0605, CVE-2020-0606, CVE-2020-0646)
- 서비스 거부 취약점(CVE-2020-0602)
o 영향 : 원격코드실행
o 중요도 : 긴급
o 관련 KB번호
- 4532933, 4532935, 4532936, 4532938, 4534271, 4534276, 4534293, 4534306, 4534976, 4534977, 4534978, 4534979, 4535101, 4535102, 4535103, 4535104, 4535105
##### □ 해결책
o 영향 받는 소프트웨어를 이용하는 경우 마이크로소프트사의 보안 패치 적용
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.
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
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-91 · XML Injection (aka Blind XPath Injection)
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-2020-2140
Product sourceCISA KEV
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD enriched
Core structured fields are present and their contributing authorities are shown above.
Affected versionsThe structured affected or fixed version information changed.
Before
Windows 7 for 32-bit Systems Service Pack 1; Windows 7 for x64-based Systems Service Pack 1; Windows 8.1 for 32-bit systems; Windows 8.1 for x64-based systems; Windows RT 8.1; Windows Server 2008 R2 for x64-based Systems Service Pack 1; Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation); Windows Server 2012 · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
After
Microsoft .NET Framework 4.6/4.6.1/4.6.2/4.7/4.7.1/4.7.2: Windows 7 for 32-bit Systems Service Pack 1, Windows 7 for x64-based Systems Service Pack 1, Windows 8.1 for 32-bit systems, Windows 8.1 for x64-based systems, Windows RT 8.1, Windows Server 2008 R2 for x64-based Systems Service Pack 1, Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation), Windows Server 2012, Windows Server 2012 (Server Core installation), Windows Server 2012 R2, Windows Server 2012 R2 (Server Core installation); Microsoft .NET Framework 4.6.2/4.7/4.7.1/4.7.2: Windows 10 Version 1607 for 32-bit Systems; Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for 32-bit Systems: unspecified; Microsoft .NET Framework 4.8 on Windows 10 Version 1803 for x64-based Systems: unspecified; Microsoft .NET Framework 4.8 on Windows Server, version 1803 (Server Core Installation): unspecified; Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for 32-bit Systems: unspecified; Microsoft .NET Framework 4.8 on Windows 10 Version 1709 for x64-based Systems: unspecified; Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for 32-bit Systems: unspecified; Microsoft .NET Framework 4.8 on Windows 10 Version 1607 for x64-based Systems: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2016: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2016 (Server Core installation): unspecified; Microsoft .NET Framework 4.8 on Windows 7 for 32-bit Systems Service Pack 1: unspecified; Microsoft .NET Framework 4.8 on Windows 7 for x64-based Systems Service Pack 1: unspecified; Microsoft .NET Framework 4.8 on Windows 8.1 for 32-bit systems: unspecified; Microsoft .NET Framework 4.8 on Windows 8.1 for x64-based systems: unspecified; Microsoft .NET Framework 4.8 on Windows RT 8.1: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2008 R2 for x64-based Systems Service Pack 1: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation): unspecified; Microsoft .NET Framework 4.8 on Windows Server 2012: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2012 (Server Core installation): unspecified; Microsoft .NET Framework 4.8 on Windows Server 2012 R2: unspecified; Microsoft .NET Framework 4.8 on Windows Server 2012 R2 (Server Core installation): unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for 32-bit Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1809 for x64-based Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019: unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows Server 2019 (Server Core installation): unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1903 for 32-bit Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows 10 Version 1903 for x64-based Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.8 on Windows Server, version 1903 (Server Core installation): 1903; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for 32-bit Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows 10 Version 1809 for x64-based Systems: unspecified; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019: unspecified; Microsoft .NET Framework 3.5 AND 4.7.2 on Windows Server 2019 (Server Core installation): unspecified; Microsoft .NET Framework 4.6: Windows Server 2008 for 32-bit Systems Service Pack 2, Windows Server 2008 for x64-based Systems Service Pack 2; Microsoft .NET Framework 3.0: Service Pack 2 on Windows Server 2008 for 32-bit Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for Itanium-Based Systems Service Pack 2, Service Pack 2 on Windows Server 2008 for x64-based Systems Service Pack 2; 17 additional product groups retained in the authoritative source · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
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.
BlackTreeCVE Intelligence