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Full vulnerability report · 2021
CVE-2021-27074High confidence

Azure Sphere Unsigned Code Execution Vulnerability

Microsoft · Azure Sphere

6.2MediumCVSS 3.1
Recommended action
Within 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • EPSS is 1.31% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Microsoft Azure Sphere and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

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-2021-13845

No EUVD known-exploited evidence

Azure Sphere Unsigned Code Execution Vulnerability

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
6.2 · CVSS 3.1
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

Azure Sphere Unsigned Code Execution Vulnerability

What

Azure Sphere Unsigned Code Execution Vulnerability

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

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

What

Azure Sphere Unsigned Code Execution Vulnerability

Why

The current structured CVE record identifies a security weakness, but the root cause requires confirmation in the linked vendor material.

How

An attacker operating through local access may attempt exploitation without authentication or 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.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

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
local access → vulnerable operation → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
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.
CWE not yet assigned
CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N/E:P/RL:O/RC:C

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

AVLocalAttack vector: The attacker needs local access to the vulnerable system.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.CNoneConfidentiality impact: No direct loss is represented by this metric.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
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
UnauthenticatedPublic exploit reference
A

Official authority intelligence

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

ENISA EUVD · EUVD-2021-13845Official EUVD mapping

Azure Sphere Unsigned Code Execution Vulnerability

Official EUVD record ↗
Cyber Security Agency of Singapore · English · CSA-SB-20210317Security Bulletin 17 Mar 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 17 Mar 2021, published on 17 March 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-182Multiples vulnérabilités dans les produits Microsoft

d?id=CVE-2021-27053 Référence CVE CVE-2021-27054 https://www.cve.org/CVERecord?id=CVE-2021-27054 Référence CVE CVE-2021-27055 https://www.cve.org/CVERecord?id=CVE-2021-27055 Référence CVE CVE-2021-27056 https://www.cve.org/CVERecord?id=CVE-2021-27056 Référence CVE CVE-2021-27057 https://www.cve.org/CVERecord?id=CVE-2021-27057 Référence CVE CVE-2021-27058 https://www.cve.org/CVERecord?id=CVE-2021-27058 Référence CVE CVE-2021-27060 https://www.cve.org/CVERecord?id=CVE-2021-27060 Référence CVE CVE-2021-27061 https://www.cve.org/CVERecord?id=CVE-2021-27061 Référence CVE CVE-2021-27062 https://www.cve.org/CVERecord?id=CVE-2021-27062 Référence CVE CVE-2021-27074 https://www.cve.org/CVERecord?id=CVE-2021-27074 Référence CVE CVE-2021-27075 https://www.cve.org/CVERecord?id=CVE-2021-27075 Référence CVE CVE-2021-27076 https://www.cve.org/CVERecord?id=CVE-2021-27076 Référence CVE CVE-2021-27080 https://www.cve.org/CVERecord?id=CVE-2021-27080 Référence CVE CVE-2021-27081 https://www.cve.org/CVERecord?id=CVE-2021-27081 Référence CVE CVE-2021-27082 https://www.cve.org/CVERecord?id=CVE-2021-27082 Référence CVE CVE-2021-27083 https://www.cve.org/CVERecord?id=CVE-2021-27083 Référence CVE CVE-2021-27084 https://www.cve.org/CVERecord?id=CVE-2021-27084 Gestion détaillée du document le 10 mars 2021 Version initiale

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-001242Azure Sphere における未署名のコードを実行される脆弱性

Azure Sphere には、未署名のコードを実行される脆弱性が存在します。 本脆弱性は、CVE-2021-27074 とは異なる脆弱性です。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-001238Azure Sphere における未署名のコードを実行される脆弱性

Azure Sphere には、未署名のコードを実行される脆弱性が存在します。 本脆弱性は、CVE-2021-27080 とは異なる脆弱性です。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-5282MS 3월 보안 위협에 따른 정기 보안 업데이트 권고

3231, 4493232, 4493238 Power BI 보고 서버 중요 정보 유출 5001284, 5001285 Azure 관련 소프트웨어 긴급 원격 코드 실행 - Microsoft Visual Studio 관련 소프트웨어 긴급 원격 코드 실행 - Windows 관리 센터 중요 보안 기능 우회 - HEVC 비디오 확장 긴급 원격 코드 실행 - [참고 사이트] [1] (한글) https://portal.msrc.microsoft.com/ko-kr/security-guidance [2] (영문) https://portal.msrc.microsoft.com/en-us/security-guidance [3] https://msrc.microsoft.com/update-guide/releaseNote/2021-Mar o 취약점 요약 정보 제품 카테고리 CVE 번호 CVE 제목 .NET Core CVE-2021-26701 .NET Core 원격 코드 실행 취약성 Application Virtualization CVE-2021-26890 응용 프로그램 가상화 원격 코드 실행 취약성 Azure CVE-2021-27075 Azure 가상 컴퓨터 정보 유출 취약성 Azure Sphere CVE-2021-27080 Azure Sphere 미서명 코드 실행 취약성 CVE-2021-27074 Azure Sphere 미서명 코드 실행 취약성 Internet Explorer CVE-2021-27085 Internet Explorer 원격 코드 실행 취약성 CVE-2021-26411 Internet Explorer 메모리 손상 취약성 Microsoft ActiveX CVE-2021-26869 Windows ActiveX 설치 관리자 서비스 정보 유출 취약성 Microsoft Exchange Server CVE-2021-27065 Microsoft Exchange Server 원격 코드 실행 취약성 CVE-2021-26858 Microsoft Exchange Server 원격 코드 실행 취약성 CVE-2021-26857 Microsoft Exchange Server 원격 코드 실행 취약성 CVE-2021-26855 Microsoft Exchange Server 원격 코드 실행 취약성 Microsoft Graphics Component CVE-2021-27077 Windows Win32k 권한 상승 취약성 CVE-2021-26876 OpenType 글꼴 구문 분석 원격 코드 실행 취약성 CVE-2021-26875 Windows Win32k 권한 상승 취약성 CVE-2021-26868 Windows 그래픽 구성 요소 권한 상승 취약성 CVE-

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
Azure Sphere: -
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.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 11 Mar 2021 · Last source change 19 Aug 2026, 16:30 UTC · CWE not yet assigned

CVE recordCVE.org · 5.2
CVSS sourceCNA
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-2021-13845
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceUnavailable
NVD statusNVD modified after enrichment

Missing structured fields: CWE classification. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Vendor guidanceAuthoritative vendor guidance changed: added remediation: portal.msrc.microsoft.com/CVE-2021-27074; removed patch: msrc.microsoft.com/CVE-2021-27074; removed remediation: msrc.microsoft.com/CVE-2021-27074.
    Before
    patch: msrc.microsoft.com/CVE-2021-27074 · patch: portal.msrc.microsoft.com/CVE-2021-27074 · remediation: msrc.microsoft.com/CVE-2021-27074
    After
    patch: portal.msrc.microsoft.com/CVE-2021-27074 · remediation: portal.msrc.microsoft.com/CVE-2021-27074
    portal.msrc.microsoft.com ↗
  2. Vendor guidanceAuthoritative vendor guidance changed: added patch: msrc.microsoft.com/CVE-2021-27074; added remediation: msrc.microsoft.com/CVE-2021-27074; removed remediation: portal.msrc.microsoft.com/CVE-2021-27074.
    Before
    patch: portal.msrc.microsoft.com/CVE-2021-27074 · remediation: portal.msrc.microsoft.com/CVE-2021-27074
    After
    patch: msrc.microsoft.com/CVE-2021-27074 · patch: portal.msrc.microsoft.com/CVE-2021-27074 · remediation: msrc.microsoft.com/CVE-2021-27074
    msrc.microsoft.com ↗
  3. Affected versionsThe structured affected or fixed version information changed.
    Before
    N/A · 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
    - · 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.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-13845↗Patch or update reference↗CVE authority or vendor reference↗Public exploit reference↗Public exploit 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-2021-27074 · cve.blacktree.nl