CVE-2023-22736 — v2
HIGHCVE-2023-22736 is a high-severity (CVSS 8.5) CWE-862 vulnerability in github.com/argoproj/argo-cd/v2. A fix is available for github.com/argoproj/argo-cd/v2 — see the affected versions and patch details below.
argo-cd Controller reconciles apps outside configured namespaces when sharding is enabled
Exploitation Status
No confirmed exploitation observed yet
- A successful exploit gives an attacker total control of the affected component, not partial access.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2023-22736.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-22736 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
github.com/argoproj/argo-cd/v2🐹github.com/argoproj/argo-cd/v2Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
Impact
All Argo CD versions starting with 2.5.0-rc1 are vulnerable to an authorization bypass bug which allows a malicious Argo CD user to deploy Applications outside the configured allowed namespaces.
Description of exploit
Reconciled Application namespaces are specified as a comma-delimited list of glob patterns. When sharding is enabled on the Application controller, it does not enforce that list of patterns when reconciling Applications. For example, if Application namespaces are configured to be argocd-*, the Application controller may reconcile an Application installed in a namespace called other, even though it does not start with argocd-.
Reconciliation of the out-of-bounds Application is only triggered when the Application is updated, so the attacker must be able to cause an update operation on the Application resource.
Limitations
This bug only applies to users who have explicitly enabled the "apps-in-any-namespace" feature by setting application.namespaces in the argocd-cmd-params-cm ConfigMap or otherwise setting the --application-namespaces flags on the Application controller and API server components. The apps-in-any-namespace feature is in beta as of this Security Advisory's publish date.
The bug is also limited to Argo CD instances where sharding is enabled by increasing the replicas count for the Application controller.
Finally, the AppProjects' sourceNamespaces field acts as a secondary check against this exploit. To cause reconciliation of an Application in an out-of-bounds namespace, an AppProject must be available which permits Applications in the out-of-bounds namespace.
Patches
A patch for this vulnerability has been released in the following Argo CD versions:
- v2.5.8
- v2.6.0-rc5
Workarounds
Running only one replica of the Application controller will prevent exploitation of this bug.
Making sure all AppProjects' sourceNamespaces are restricted within the confines of the configured Application namespaces will also prevent exploitation of this bug.
Credits
Thanks to ChangZhuo Chen (@czchen) for finding the issue and for contributing the fix!
References
For more information
- Open an issue in the Argo CD issue tracker or discussions
- Join us on Slack in channel #argo-cd
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/argoproj/argo-cd/v2 | ≥ 2.5.0-rc1&&< 2.5.8 | 2.5.8go get github.com/argoproj/argo-cd/v2@v2.5.8 |
| 🐹Go | github.com/argoproj/argo-cd/v2 | ≥ 2.6.0-rc4&&< 2.6.0-rc5 | 2.6.0-rc5go get github.com/argoproj/argo-cd/v2@v2.6.0-rc5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/argoproj/argo-cd/v2, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/argoproj/argo-cd/v2 to 2.5.8 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-22736 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-22736 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-22736. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
This issue only affects Red Hat GitOps version 1.7, as the vulnerability was introduced in ArgoCD-2.5. This vulnerability affects only deployments with "apps-in-any-namespace" feature by setting application.namespaces in the argocd-cmd-params-cm ConfigMap or otherwise setting the --application-namespaces flags on the…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat OpenShift GitOps 1.7 | openshift-gitops-1/argocd-rhel8:v1.7.1-2 | RHSA-2023:0467 |
Frequently Asked Questions
Is CVE-2023-22736 in your dependencies?
O3 Security finds CVE-2023-22736 across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.