CVE-2026-54030
LibreChat: Missing Resource Parameter Validation in MCP OAuth Flow
Description
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.
INFO
Published Date :
June 25, 2026, 5:16 p.m.
Last Modified :
June 29, 2026, 11:55 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | CRITICAL | [email protected] |
Solution
- Update LibreChat to version 0.8.5.
- Validate MCP OAuth resource parameter configuration.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-54030.
| URL | Resource |
|---|---|
| https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 | Exploit Vendor Advisory |
| https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 | Exploit Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-54030 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-54030
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-54030 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-54030 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 29, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N Added CPE Configuration OR *cpe:2.3:a:librechat:librechat:*:*:*:*:*:*:*:* versions up to (including) 0.8.4 *cpe:2.3:a:librechat:librechat:0.8.5:rc1:*:*:*:*:*:* Added Reference Type GitHub, Inc.: https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 Types: Exploit, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 Types: Exploit, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 26, 2026
Action Type Old Value New Value Added Reference https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23 Added SSVC {'id': 'CVE-2026-54030', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-06-26T02:04:27.570333Z'} -
New CVE Received by [email protected]
Jun. 25, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'danny-avila', 'product': 'LibreChat', 'versions': [{'status': 'affected', 'version': '< 0.8.5'}]}] Added Description 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. Added CVSS V3.1 AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N Added CWE CWE-346 Added Reference https://github.com/danny-avila/LibreChat/security/advisories/GHSA-gvpj-vm2f-2m23