CyberSecBulletin
CVE-2023-22736NVD status: Modified

argo-cd: Missing Authorization

Published Updated By the CyberSecBulletin desk

CVE-2023-22736 is a high-severity missing authorization vulnerability in argo-cd from Argoproj, with a CVSS 3.1 base score of 8.5 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected argo-cd versions: >= 2.5.0=rc1, < 2.5.8; = 2.6.0-rc4, < 2.6.0-rc5. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.8% chance of exploitation within 30 days, higher than 57% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of argo-cd you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
Argoprojargo-cd>= 2.5.0=rc1, < 2.5.8; = 2.6.0-rc4, < 2.6.0-rc5Not stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.5HighCNA (github.com)
CVSS 3.18.5HighNVD

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Missing Authorization

The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

How developers prevent this class of flaw

  • Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.

More Missing Authorization vulnerabilities (CWE-862)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in argo-cd

All argo-cd vulnerabilities

Recent Missing Authorization vulnerabilities

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