Argoproj: >> Argo Cd >> 2.5.5 Security Vulnerabilities
Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Versions starting with 2.5.0-rc1 and above, prior to 2.5.8, and version 2.6.0-rc4, are vulnerable to an authorization bypass bug which allows a malicious Argo CD user to deploy Applications outside the configured allowed namespaces. 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. 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. A patch for this vulnerability has been released in versions 2.5.8 and 2.6.0-rc5. As a workaround, 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.
CVSS Score
8.5
EPSS Score
0.0
Published
2023-01-26
Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Versions of Argo CD starting with v1.8.2 and prior to 2.3.13, 2.4.19, 2.5.6, and 2.6.0-rc-3 are vulnerable to an improper authorization bug causing the API to accept certain invalid tokens. OIDC providers include an `aud` (audience) claim in signed tokens. The value of that claim specifies the intended audience(s) of the token (i.e. the service or services which are meant to accept the token). Argo CD _does_ validate that the token was signed by Argo CD's configured OIDC provider. But Argo CD _does not_ validate the audience claim, so it will accept tokens that are not intended for Argo CD. If Argo CD's configured OIDC provider also serves other audiences (for example, a file storage service), then Argo CD will accept a token intended for one of those other audiences. Argo CD will grant the user privileges based on the token's `groups` claim, even though those groups were not intended to be used by Argo CD. This bug also increases the impact of a stolen token. If an attacker steals a valid token for a different audience, they can use it to access Argo CD. A patch for this vulnerability has been released in versions 2.6.0-rc3, 2.5.6, 2.4.19, and 2.3.13. There are no workarounds.
CVSS Score
9.0
EPSS Score
0.003
Published
2023-01-26
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