CVE-2026-54030
LibreChat: Missing Resource Parameter Validation in MCP OAuth Flow
CVSS Score
8.0
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-346 |
| Vendor | danny-avila |
| Product | librechat |
| Published | Jun 25, 2026 |
| Last Updated | Jun 26, 2026 |
Stay Ahead of the Next One
Get instant alerts for danny-avila librechat
Be the first to know when new high vulnerabilities affecting danny-avila librechat are published — delivered to Slack, Telegram or Discord.
Get Free Alerts →
Free · No credit card · 60 sec setup
CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:N Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
Required
Scope
Changed
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
danny-avila / LibreChat
< 0.8.5