CVE-2026-45723: siderolabs omni Improper Input Validation

Vulnerability summary

CVE-2026-45723 is a low (CVSS 2.7) Improper Input Validation vulnerability in siderolabs omni. EPSS estimates a 0.49% chance of exploitation in the next 30 days, higher than 41.1% of scored vulnerabilities.

Timeline

1. 17-09-2026
   PublishedVulnerability first disclosed.
2. 18-09-2026
   Last modifiedVulnerability information updated.

Description

Omni manages Kubernetes on bare metal, virtual machines, or in a cloud. Prior to 1.6.6 and 1.7.3, managementServer.CreateSchematic in internal/backend/grpc/schematics.go passes the caller-controlled TalosVersion field to imageFactoryClient.OverlaysVersions without validating it as a version. An authenticated Operator can submit traversal segments in TalosVersion, and url.URL.JoinPath normalizes them into unintended paths on the configured image-factory host. Omni then issues HTTP GET requests to those paths and reflects error-body content, enabling same-host endpoint probing and possible disclosure of internal diagnostics while preventing redirection to another host or write requests. This issue is fixed in versions 1.6.6 and 1.7.3.

• CWE-20Improper Input ValidationThe product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly.
• CWE-22Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
• CWE-209Generation of Error Message Containing Sensitive InformationThe product generates an error message that includes sensitive information about its environment, users, or associated data.
• CWE-441Unintended Proxy or Intermediary ('Confused Deputy')The product receives a request, message, or directive from an upstream component, but the product does not sufficiently preserve the original source of the request before forwarding the request to an external actor that is outside of the product's control sphere. This causes the product to appear to be the source of the request, leading it to act as a proxy or other intermediary between the upstream component and the external actor.
• CWE-918Server-Side Request Forgery (SSRF)The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination.