CVE-2026-42880 ArgoCD ServerSideDiff is vulnerable to Kubernetes Secret Extraction
Attackers with read-only access can extract plaintext Kubernetes Secrets via the ServerSideDiff endpoint due to missing authorization and data masking.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-42880?
CVE-2026-42880 is a critical missing authorization vulnerability in Argoproj Argo Cd, published on 7 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. From versions 3.2.0 to before 3.2.11 and 3.3.0 to before 3.3.9, there is a missing authorization and data-masking gap in Argo CD's ServerSideDiff endpoint that allows an attacker with read-only access to extract plaintext Kubernetes Secret data from etcd via the Kubernetes API server's Server-Side Apply dry-run mechanism. This issue has been patched in versions 3.2.11 and 3.3.9.
Which versions are affected by CVE-2026-42880?
It affects 1 product.
Products include Argoproj Argo Cd.
How do I fix CVE-2026-42880?
Upgrade to a fixed version.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-42880 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-42880 exists.
Public exploit code: 1 proofs of concept on GitHub.
Other vulnerabilities in Argoproj Argo Cd
- CVE-2025-55190 Argo CD: Project API Token Exposes Repository Credentials
- CVE-2022-29165 Argo CD will blindly trust JWT claims if anonymous access is enabled
- CVE-2023-40029 Cluster secret might leak in cluster details page in Argo CD
- CVE-2022-24768 Improper access control allows admin privilege escalation in Argo CD
- CVE-2024-21652 Argo CD vulnerable to Bypassing of Brute Force Protection via Application Crash and In-Memory Data Loss
Sources
Also known as CLEANSTART-2026-MB60182, CLEANSTART-2026-QR94523, MINI-2953-4rgg-pg7p, MINI-5cx5-wrrx-gmm2, MINI-5rpx-vxj7-9mw4, MINI-5wj2-2gx9-6ghj and 10 more.