Vulnerability · Published Sep 13, 2022 · Assigned by GitHub_M
CVE-2022-36103Talos worker join token can be used to get elevated access level to the Talos API
High 7.2
In plain English
A high-severity incorrect permission assignment in talos from siderolabs. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 53% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Talos Linux is a Linux distribution built for Kubernetes deployments. Talos worker nodes use a join token to get accepted into the Talos cluster. Due to improper validation of the request while signing a worker node CSR (certificate signing request) Talos control plane node might issue Talos API certificate which allows full access to Talos API on a control plane node. Accessing Talos API with full level access on a control plane node might reveal sensitive information which allows full level access to the cluster (Kubernetes and Talos PKI, etc.). Talos API join token is stored in the machine configuration on the worker node. When configured correctly, Kubernetes workloads don't have access to the machine configuration, but due to a misconfiguration workload might access the machine configuration and reveal the join token. This problem has been fixed in Talos 1.2.2. Enabling the Pod Security Standards mitigates the vulnerability by denying hostPath mounts and host networking by default in the baseline policy. Clusters that don't run untrusted workloads are not affected. Clusters with correct Pod Security configurations which don't allow hostPath mounts, and secure access to cloud metadata server (or machine configuration is not supplied via cloud metadata server) are not affected.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/talos-systems/talos | 1.2.2 | GHSA-7hgc-php5-77qq |
| Go | github.com/talos-systems/talos | 1.2.2 | GO-2022-0995 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| siderolabs | talos | < 1.2.2 |
Weakness: CWE-732 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
References
- https://github.com/siderolabs/talos/security/advisories/GHSA-7hgc-php5-77qq x_refsource_CONFIRM
- https://github.com/siderolabs/talos/commit/9eaf33f3f274e746ca1b442c0a1a0dae0cec088f x_refsource_MISC
- https://github.com/siderolabs/talos/releases/tag/v1.2.2 x_refsource_MISC