What is CVE-2026-54030?

CVE-2026-54030 is a high-severity vulnerability in Danny-Avila Librechat, classified under Origin Validation Error. CVSS score: 8.0/10. Published 2026-06-25.

How severe is CVE-2026-54030?

High severity. CVSS v3 base score is 8.0 out of 10.

Vulnerability in Danny-Avila Librechat

CVE-2026-54030

LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.5, LibreChat's MCP OAuth implementation does not validate that the resource parameter from OAuth Protected Resource metadata (RFC 9728) matches the configured MCP server URL, allowing a malicious MCP server to steal access tokens intended for a legitimate server. This vulnerability is fixed in 0.8.5.

Published 2026-06-25 · last modified 2026-06-29.

CVSS v3 metric

CVSS v3 base score 8.0 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.002 (5.4th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 5th percentile — 5.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000

Affected products

Danny-Avila Librechat — versions < 0.8.5
Librechat — versions 0.8.5

Weakness classification (CWE)

CWE-346 — Origin Validation Error

References

github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 (Exploit, Vendor Advisory)

Frequently asked questions

What is CVE-2026-54030?: CVE-2026-54030 is a high-severity vulnerability in Danny-Avila Librechat, classified under Origin Validation Error. CVSS score: 8.0/10. Published 2026-06-25.
How severe is CVE-2026-54030?: High severity. CVSS v3 base score is 8.0 out of 10.