CVE-2026-54027: CWE-862: Missing Authorization in danny-avila LibreChat
LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.4-rc1, the POST /api/files/images endpoint allows any authenticated user to upload files into any agent's tool_resources (e.g., context, execute_code) without verifying ownership or EDIT permission on the target agent. A permission check was added to the POST /api/files route in a previous patch, but the image upload route was never updated with the same check. An attacker can simply use the image endpoint instead of the file endpoint to bypass the authorization entirely. This vulnerability is fixed in 0.8.4-rc1.
AI Analysis
Technical Summary
CVE-2026-54027 is a missing authorization vulnerability (CWE-862) in danny-avila's LibreChat. Specifically, before version 0.8.4-rc1, the POST /api/files/images endpoint does not verify whether the authenticated user has ownership or edit permissions on the target agent's tool_resources, allowing unauthorized file uploads. Although a permission check was implemented on the POST /api/files route, the image upload endpoint was overlooked, enabling attackers to bypass authorization by using the image endpoint instead. The vulnerability is addressed in version 0.8.4-rc1.
Potential Impact
An attacker with authenticated access can upload files to any agent's tool_resources without proper authorization, potentially modifying or injecting malicious content into the agent's context or code execution environment. This could lead to unauthorized manipulation of agent behavior or other integrity impacts. Confidentiality and availability are not affected according to the CVSS vector.
Mitigation Recommendations
This vulnerability is fixed in LibreChat version 0.8.4-rc1. Users should upgrade to version 0.8.4-rc1 or later to ensure the authorization checks are properly enforced on the image upload endpoint. No other mitigation steps are indicated in the vendor data.
CVE-2026-54027: CWE-862: Missing Authorization in danny-avila LibreChat
Description
LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.4-rc1, the POST /api/files/images endpoint allows any authenticated user to upload files into any agent's tool_resources (e.g., context, execute_code) without verifying ownership or EDIT permission on the target agent. A permission check was added to the POST /api/files route in a previous patch, but the image upload route was never updated with the same check. An attacker can simply use the image endpoint instead of the file endpoint to bypass the authorization entirely. This vulnerability is fixed in 0.8.4-rc1.
CVSS v3.1
Score 6.5medium
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-2026-54027 is a missing authorization vulnerability (CWE-862) in danny-avila's LibreChat. Specifically, before version 0.8.4-rc1, the POST /api/files/images endpoint does not verify whether the authenticated user has ownership or edit permissions on the target agent's tool_resources, allowing unauthorized file uploads. Although a permission check was implemented on the POST /api/files route, the image upload endpoint was overlooked, enabling attackers to bypass authorization by using the image endpoint instead. The vulnerability is addressed in version 0.8.4-rc1.
Potential Impact
An attacker with authenticated access can upload files to any agent's tool_resources without proper authorization, potentially modifying or injecting malicious content into the agent's context or code execution environment. This could lead to unauthorized manipulation of agent behavior or other integrity impacts. Confidentiality and availability are not affected according to the CVSS vector.
Mitigation Recommendations
This vulnerability is fixed in LibreChat version 0.8.4-rc1. Users should upgrade to version 0.8.4-rc1 or later to ensure the authorization checks are properly enforced on the image upload endpoint. No other mitigation steps are indicated in the vendor data.
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: 6a3d5b504853345fc1337283
Added to database: 06/25/2026, 16:46:08 UTC
Last enriched: 06/25/2026, 17:02:29 UTC
Last updated: 06/26/2026, 00:42:45 UTC
Views: 4
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