CVE-2026-125331

Summary

In HarnessRouter versions prior to 0.31.8, non-self-hosted deployments incorrectly attach the server's internal authorization key to requests before validating the provided bearer token, and certain API routes trust this key to derive organization context from the URL. This allows unauthenticated attackers to forge requests that impersonate any organization and modify provider connections, leading to credential theft and injection of malicious responses into agent workflows.

Exploitability

Exploitation is straightforward for remote attackers with network access, requiring only knowledge of the vulnerable endpoints and ability to craft malformed Authorization headers; no prior authentication or privileged access is needed.

Blast radius

Successful exploitation enables cross-tenant data exfiltration and command injection into agent tasks across organizations in multi-tenant deployments, potentially compromising all tenants sharing the same instance.

Detection

Defenders should monitor for anomalous PUT/GET requests to /v1/orgs/{org}/connections/{name}, /v1/orgs/{org}/policy/{backend}, or /internal/* paths where the Authorization header contains a non-standard or malformed bearer token, especially when paired with suspicious organization IDs not matching known internal usage patterns.

Prioritized remediation

Upgrade to HarnessRouter version 0.31.8 immediately to patch the authentication bypass and authorization flaw.

Analysis generated locally by garnet-coder (no data left the box). AI-assisted — verify against primary sources before acting.