CVE-2026-65700: h2oGPT 0.2.1 Path Traversal via OpenAI-compatible Files API

Vulnerability summary

CVE-2026-65700 is a critical (CVSS 9.8) vulnerability in h2oai h2ogpt. EPSS estimates a 1.52% chance of exploitation in the next 30 days, higher than 74.5% of scored vulnerabilities. 1 public exploit is recorded.

Timeline

1. 23-07-2026
   PublishedVulnerability first disclosed.
2. 27-07-2026
   Last modifiedVulnerability information updated.

Description

h2oGPT through 0.2.1 contains a path traversal vulnerability in the OpenAI-compatible files API that allows unauthenticated remote attackers to read, write, and delete arbitrary files accessible to the server process by supplying traversal sequences in the bearer token. The get_user_dir function in openai_server/backend_utils.py uses the bearer token string unsanitized as a path component via os.path.join, and because the default API key is EMPTY authentication is bypassed, enabling attackers to traverse outside the intended user directory through the file content, delete, and upload endpoints to achieve remote code execution by writing to startup hooks or application-loaded files.

• CWE-22Improper Limitation of a Pathname to a Restricted DirectoryThe 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.