h2oGPT 0.2.1 Path Traversal via OpenAI-compatible Files API

published 2026-07-23 3 mo ago modified 2026-10-24 15 d ago also EUVD-2026-48332

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.5%; EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits: 0; none known

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.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: yes
Technical impact: total
Assessed: 3 mo ago (2026-07-27)

Exploit prediction

1.52% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

github.com https://github.com/geo-chen/oss/blob/main/h2ogpt.md referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA	4.0	9.3	CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

h2oai h2ogpt

Classification

Weakness

CWE-22 Improper Limitation of a Pathname to a Restricted Directory

References

github.com /geo-chen/oss/blob/main/h2ogpt.md
technical-description, exploit
vulncheck.com /advisories/h2ogpt-path-traversal-via-openai-compatible-files-api
third-party-advisory

Sources

CVE List CVE-2026-65700
NVD CVE-2026-65700

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary