CVE-2026-73842: OpenChoreo: cluster-gateway internal proxy performs no caller authentication and is not read-only — data-plane Secret disclosure and arbitrary Kubernetes mutation

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
• EPSS 0.3%, percentile 18: FIRST’s model estimates a 0.3% chance of exploitation activity in the next 30 days, higher than 18% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes github.com/openchoreo/openchoreo (Go) < 1.0.3, fixed in 1.0.3; github.com/openchoreo/openchoreo (Go) >= 1.1.0, < 1.1.3, fixed in 1.1.3; github.com/openchoreo/openchoreo (Go) >= 1.2.0-rc.1, < 1.2.0-rc.2, fixed in 1.2.0. Check your lockfile, including transitive dependencies.

What it is

OpenChoreo is a complete, open-source developer platform for Kubernetes. Prior to 1.0.3, 1.1.3, and 1.2.0-rc.2, internal/cluster-gateway/server.go exposed /api/proxy/, /api/exec/, and /api/wirelogs/ on an internal listener without requiring a client certificate or token, allowing any network-reachable caller to read tenant Kubernetes Secrets, mutate workloads, and execute commands across connected data planes. This issue is fixed in versions 1.0.3, 1.1.3, and 1.2.0-rc.2.

From the GitHub advisory

Summary

The OpenChoreo control-plane cluster-gateway exposes internal management APIs (/api/proxy/, /api/exec/, /api/wirelogs/) that tunnel requests through to connected data planes' Kubernetes APIs, but the internal listener authenticates no caller. Its request validator permits mutating HTTP methods and reads of Secrets in tenant namespaces (only kube-system Secrets are blocked), so although the client library documents these requests as "read-only," the server enforces no such restriction. Any party able to reach the internal listener can — with no client certificate or token — read Secrets in any tenant namespace, create/modify/delete workloads, and exec into pods across every connected data plane.

Impact

An attacker with network access to the cluster-gateway internal listener obtains tunneled access to every connected data plane's Kubernetes API with no caller-level access control. Across all connected data planes, this allows:

- Secret disclosure — reading any Secret outside kube-system in any tenant namespace (database credentials, cloud/KMS keys, TLS private keys), independent of any workload ServiceAccount permissions. - Workload tampering or destruction — creating, modifying, or deleting Deployments, Services, and other resources. - Pod command execution inside workload pods via /api/exec/.

Weakness type: CWE-269, CWE-306, CWE-862.

Product: github.com/openchoreo/openchoreo (Go) · Assigned by: GitHub_M · Published: 2026-08-13

Affected and fixed versions

Severity scores

• Attack vector: adjacent network only
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation none, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.27% probability of exploitation activity in the next 30 days; percentile 18.

Timeline

• 2026-08-13 — CVE record published by GitHub_M
• 2026-08-18 — CVE record last updated
• 2026-09-04 — GitHub-reviewed advisory GHSA-rh53-xvx2-j327 published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-rh53-xvx2-j327 github.com
2. CVE.org record CVE-2026-73842 cve.org
3. NVD entry CVE-2026-73842 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com
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10. github.com github.com

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