CWE-1220Weakness · CWE-1220

CVE-2026-6388

CRITICAL · 9.1 CVSS v3.1 Published 2026-04-15
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
97/100
Remediation priority · Urgent
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
A flaw was found in ArgoCD Image Updater. This vulnerability allows an attacker, with permissions to create or modify an ImageUpdater resource in a multi-tenant environment, to bypass namespace boundaries. By exploiting insufficient validation, the attacker can trigger unauthorized image updates on applications managed by other tenants. This leads to cross-namespace privilege escalation, impacting application integrity through unauthorized application updates.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

ArgoCD Image Updater has insufficient namespace boundary validation that allows attackers with permissions to create or modify ImageUpdater resources to bypass namespace isolation in multi-tenant environments, enabling cross-namespace privilege escalation and unauthorized image updates on applications managed by other tenants.

MitigationApply proper namespace boundary validation to ensure ImageUpdater resources can only affect applications within their own namespace, and review RBAC policies to restrict ImageUpdater permissions appropriately in multi-tenant setups.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Changed
Confidentiality
Low
Integrity
High
Availability
Low

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:H/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify if ArgoCD Image Updater is installed
    Run 'kubectl get pods -A | grep -i argocd-image-updater' or check for the argocd-image-updater deployment in any namespace
    Affected if No ArgoCD Image Updater pods or deployments found means the product is not present
  2. Verify ImageUpdater CRD exists
    Run 'kubectl get crd | grep -i imageupdater' to confirm the custom resource definition is registered
    Affected if No ImageUpdater CRD indicates the vulnerable custom resource type is not in use
  3. List all ImageUpdater resources in the cluster
    Run 'kubectl get imageupdater -A' or 'kubectl get imageupdater --all-namespaces' to see all instances across namespaces
    Affected if No ImageUpdater resources exist means the attack surface is not present
  4. Check for cross-namespace ImageUpdater references
    Review each ImageUpdater resource's spec: run 'kubectl get imageupdater -A -o yaml' and inspect the 'applications' or 'applicationsets' fields for references to namespaces different from where the ImageUpdater resides
    Affected if ImageUpdater in namespace A references applications in namespace B (where A != B)
  5. Inspect RBAC for ImageUpdater permissions
    Run 'kubectl auth can i create imageupdater' and review ClusterRole/Role bindings that grant create/modify permissions on ImageUpdater resources to non-admin users
    Affected if Tenants or non-privileged users have create/modify permissions on ImageUpdater resources across multiple namespaces

A user is affected if ArgoCD Image Updater is installed AND ImageUpdater resources exist that reference applications in namespaces other than their own, allowing cross-tenant modification.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply proper namespace boundary validation to ensure ImageUpdater resources can only affect applications within their own namespace, and review RBAC policies to restrict ImageUpdater permissions appropriately in multi-tenant setups.

Have this fixed Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing3.0 h
  • Review / QA2.0 h
14.0 hours of engineering $2,490
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,984.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-6388 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2026-6388 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data