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Full vulnerability report · 2025
CVE-2025-64432High confidence

KubeVirt Affected by an Authentication Bypass in Kubernetes Aggregation Layer

kubevirt · kubevirt

Official source article: GitHub GHSA-38JW-G2QX-4286 ↗. Check the applicable product and release in the original source.

4.7MediumCVSS 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.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 0.14% 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 kubevirt kubevirt 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.

Open-source package ranges6 source-attributed ranges

These OSV and GitHub advisory ranges apply only to the named package and ecosystem. A listed fixed version is not a universal product patch or proof that an update is installed.

Ecosystem and packageAffected rangeFirst fixed versionEvidence
Gokubevirt.io/kubevirtSEMVER: introduced 0; fixed 1.5.31.5.3OSV record ↗aggregator derived · 10 Sep 2026
Gokubevirt.io/kubevirtSEMVER: introduced 1.6.0-alpha.0; fixed 1.6.11.6.1OSV record ↗aggregator derived · 10 Sep 2026
Gokubevirt.io/kubevirtSEMVER: introduced 1.7.0-alpha.0; fixed 1.7.0-rc.01.7.0-rc.0OSV record ↗aggregator derived · 10 Sep 2026
gokubevirt.io/kubevirt< 1.5.31.5.3GitHub advisory ↗upstream repository advisory · 17 Nov 2025
gokubevirt.io/kubevirt>= 1.6.0-alpha.0, < 1.6.11.6.1GitHub advisory ↗upstream repository advisory · 17 Nov 2025
gokubevirt.io/kubevirt>= 1.7.0-alpha.0, < 1.7.0-rc.01.7.0-rc.0GitHub advisory ↗upstream repository advisory · 17 Nov 2025
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-2025-38218

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

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
Not supplied in the stored EUVD record
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

KubeVirt is a virtual machine management add-on for Kubernetes. Versions 1.5.3 and below, and 1.6.0 contained a flawed implementation of the Kubernetes aggregation layer's authentication flow which could enable bypass of RBAC controls. It was discovered that the virt-api component fails to correctly authenticate the client when receiving API requests over mTLS. In particular, it fails to validate the CN (Common Name) field in the received client TLS certificates against the set of allowed values defined in the extension-apiserver-authentication configmap. Failre to validate certain fields in the client TLS certificate may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component. This issue is fixed in versions 1.5.3 and 1.6.1.

What

KubeVirt is a virtual machine management add-on for Kubernetes. Versions 1.5.3 and below, and 1.6.0 contained a flawed implementation of the Kubernetes aggregation layer's authentication flow which could enable bypass of RBAC controls. It was discovered that the virt-api component fails to correctly authenticate the client when receiving API requests over mTLS. In particular, it fails to validate the CN (Common Name) field in the received client TLS certificates against the set of allowed values defined in the extension-apiserver-authentication configmap. Failre to validate certain fields in the client TLS certificate may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component. This issue is fixed in versions 1.5.3 and 1.6.1.

Why

The affected component does not establish the requesting party's identity reliably before granting access.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

KubeVirt is a virtual machine management add-on for Kubernetes. Versions 1.5.3 and below, and 1.6.0 contained a flawed implementation of the Kubernetes aggregation layer's authentication flow which could enable bypass of RBAC controls. It was discovered that the virt-api component fails to correctly authenticate the client when receiving API requests over mTLS. In particular, it fails to validate the CN (Common Name) field in the received client TLS certificates against the set of allowed values defined in the extension-apiserver-authentication configmap. Failre to validate certain fields in the client TLS certificate may allow an attacker to bypass existing RBAC controls by directly communicating with the aggregated API server, impersonating the Kubernetes API server and its aggregator component. This issue is fixed in versions 1.5.3 and 1.6.1.

Why

The affected component does not establish the requesting party's identity reliably before granting access.

How

An attacker operating through local access may attempt exploitation with low privileges. 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 → Improper Authentication → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
High: exploitation depends on specific conditions
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-287 ↗

CWE-287: Improper Authentication. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

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:H/PR:L/UI:N/S:U/C:N/I:N/A:H

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.ACHighAttack complexity: Successful exploitation depends on specific conditions outside the attacker's direct control.PRLowPrivileges required: The attacker needs basic user-level 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.INoneIntegrity impact: No direct loss is represented by this metric.AHighAvailability impact: A successful attack can cause a major loss.
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.
CWE-287Public exploit reference
A

Official authority intelligence

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

BSI · German · WID-SEC-2025-2563Microsoft Azure Linux: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Microsoft Azure Linux und Microsoft Windows ausnutzen um erhöhte Privilegien zu erlangen, beliebigen Code auszuführen, die Authentifizierung zu umgehen, Spoofing-Angriffe durchzuführen, einen Denial-of-Service-Zustand zu verursachen oder andere, nicht näher spezifizierte Angriffe durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20251112Security Bulletin 12 Nov 2025

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 12 Nov 2025, published on 12 November 2025. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2025-020130Kubernetes 用 KubeVirt における認証に関する脆弱性

Kubernetes 用 KubeVirt には、認証に関する脆弱性、証明書検証に関する脆弱性が存在します。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-6621MS 11월 보안 위협에 따른 정기 보안 업데이트 권고

//msrc.microsoft.com/update-guide/ko-kr/releaseNote/2025-Nov o 취약점 요약 정보 (총 134개) | 제품 카테고리 | CVE 번호 | CVE 제목 | | --- | --- | --- | | Mariner | CVE-2025-64437 | KubeVirt Isolation Detection Flaw Allows Arbitrary File Permission Changes | | Mariner | CVE-2025-64436 | KubeVirt Excessive Role Permissions Could Enable Unauthorized VMI Migrations Between Nodes | | Mariner | CVE-2025-64435 | KubeVirt VMI Denial-of-Service (DoS) Using Pod Impersonation | | Mariner | CVE-2025-64434 | KubeVirt Improper TLS Certificate Management Handling Allows API Identity Spoofing | | Mariner | CVE-2025-64433 | KubeVirt Arbitrary Container File Read | | Mariner | CVE-2025-64432 | KubeVirt Affected by an Authentication Bypass in Kubernetes Aggregation Layer | | Mariner | CVE-2025-64329 | containerd CRI server: Host memory exhaustion through Attach goroutine leak | | GitHub Copilot and Visual Studio Code | CVE-2025-62453 | GitHub Copilot and Visual Studio Code Security Feature Bypass Vulnerability | | Windows Routing and Remote Access Service (RRAS) | CVE-2025-62452 | Windows RRAS(Routing and Remote Access Service) 원격 코드 실행 취약성 | | Visual Studio Code CoPilot Chat Extension | CVE-2025-62449 | Microsoft Visual Studio Code CoPilot Chat Extension Security Feature Bypass Vulnerability | | Visual Studio Code CoPilot Chat E

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
kubevirt: < 1.5.3, >= 1.6.0, < 1.6.1
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 7 Nov 2025 · Last source change 7 Nov 2025, 18:54 UTC · CWE-287 · Improper Authentication

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-2025-38218
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
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
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-2025-64432 · cve.blacktree.nl