Vulnerability · Published Sep 3, 2024 · Assigned by GitHub_M
CVE-2024-43803BMO can expose particularly named secrets from other namespaces via BMH CRD
Medium 4.9
In plain English
A medium-severity information exposure in baremetal-operator from metal3-io. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
The Bare Metal Operator (BMO) implements a Kubernetes API for managing bare metal hosts in Metal3. The `BareMetalHost` (BMH) CRD allows the `userData`, `metaData`, and `networkData` for the provisioned host to be specified as links to Kubernetes Secrets. There are fields for both the `Name` and `Namespace` of the Secret, meaning that versions of the baremetal-operator prior to 0.8.0, 0.6.2, and 0.5.2 will read a `Secret` from any namespace. A user with access to create or edit a `BareMetalHost` can thus exfiltrate a `Secret` from another namespace by using it as e.g. the `userData` for provisioning some host (note that this need not be a real host, it could be a VM somewhere). BMO will only read a key with the name `value` (or `userData`, `metaData`, or `networkData`), so that limits the exposure somewhat. `value` is probably a pretty common key though. Secrets used by _other_ `BareMetalHost`s in different namespaces are always vulnerable. It is probably relatively unusual for anyone other than cluster administrators to have RBAC access to create/edit a `BareMetalHost`. This vulnerability is only meaningful, if the cluster has users other than administrators and users' privileges are limited to their respective namespaces. The patch prevents BMO from accepting links to Secrets from other namespaces as BMH input. Any BMH configuration is only read from the same namespace only. The problem is patched in BMO releases v0.7.0, v0.6.2 and v0.5.2 and users should upgrade to those versions. Prior upgrading, duplicate the BMC Secrets to the namespace where the corresponding BMH is. After upgrade, remove the old Secrets. As a workaround, an operator can configure BMO RBAC to be namespace scoped for Secrets, instead of cluster scoped, to prevent BMO from accessing Secrets from other namespaces.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/metal3-io/baremetal-operator | 0.8.0 | GHSA-pqfh-xh7w-7h3p |
| Go | github.com/metal3-io/baremetal-operator | 0.6.2 | GHSA-pqfh-xh7w-7h3p |
| Go | github.com/metal3-io/baremetal-operator | 0.5.2 | GHSA-pqfh-xh7w-7h3p |
| Go | github.com/metal3-io/baremetal-operator | 0.5.2, 0.6.2, 0.8.0 | GO-2024-3109 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| metal3-io | baremetal-operator | >= 0.7.0, < 0.8.0>= 0.6.0, < 0.6.2< 0.5.2 |
Weakness: CWE-200, CWE-653 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
References
- https://github.com/metal3-io/baremetal-operator/security/advisories/GHSA-pqfh-xh7w-7h3p x_refsource_CONFIRM
- https://github.com/metal3-io/baremetal-operator/pull/1929 x_refsource_MISC
- https://github.com/metal3-io/baremetal-operator/pull/1930 x_refsource_MISC
- https://github.com/metal3-io/baremetal-operator/pull/1931 x_refsource_MISC
- https://github.com/metal3-io/baremetal-operator/commit/3af4882e9c5fadc1a7550f53daea21dccd271f74 x_refsource_MISC
- https://github.com/metal3-io/baremetal-operator/commit/bedae7b997d16f36e772806681569bb8eb4dadbb x_refsource_MISC
- https://github.com/metal3-io/baremetal-operator/commit/c2b5a557641bc273367635124047d6c958aa15f7 x_refsource_MISC