CVE-2026-54030: CWE-346: Origin Validation Error in danny-avila LibreChat
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.
AI Analysis
Technical Summary
CVE-2026-54030 describes an origin validation error (CWE-346) in danny-avila's LibreChat prior to version 0.8.5. The MCP OAuth implementation fails to validate that the resource parameter from OAuth Protected Resource metadata (RFC 9728) corresponds to the configured MCP server URL. This allows a malicious MCP server to intercept and steal access tokens that are meant for a legitimate MCP server. The issue is resolved in LibreChat version 0.8.5.
Potential Impact
An attacker controlling a malicious MCP server can steal OAuth access tokens intended for a legitimate MCP server. This compromises the confidentiality and integrity of user sessions and data associated with those tokens. The CVSS 3.1 score is 8.0 (High), reflecting network attack vector, high complexity, no privileges required, user interaction required, scope change, and high confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
Upgrade LibreChat to version 0.8.5 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated. Patch status is confirmed fixed in 0.8.5.
CVE-2026-54030: CWE-346: Origin Validation Error in danny-avila LibreChat
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.
CVSS v3.1
Score 8.0high
Affected software
pkg:github/danny-avila/LibreChatRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-54030 describes an origin validation error (CWE-346) in danny-avila's LibreChat prior to version 0.8.5. The MCP OAuth implementation fails to validate that the resource parameter from OAuth Protected Resource metadata (RFC 9728) corresponds to the configured MCP server URL. This allows a malicious MCP server to intercept and steal access tokens that are meant for a legitimate MCP server. The issue is resolved in LibreChat version 0.8.5.
Potential Impact
An attacker controlling a malicious MCP server can steal OAuth access tokens intended for a legitimate MCP server. This compromises the confidentiality and integrity of user sessions and data associated with those tokens. The CVSS 3.1 score is 8.0 (High), reflecting network attack vector, high complexity, no privileges required, user interaction required, scope change, and high confidentiality and integrity impact with no availability impact.
Mitigation Recommendations
Upgrade LibreChat to version 0.8.5 or later, where this vulnerability is fixed. No other mitigation or temporary workaround is indicated. Patch status is confirmed fixed in 0.8.5.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-11T16:57:50.018Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3d5b504853345fc1337289
Added to database: 06/25/2026, 16:46:08 UTC
Last enriched: 06/25/2026, 17:01:27 UTC
Last updated: 06/26/2026, 02:16:03 UTC
Views: 3
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