CVE-2026-54027CWE-862

LibreChat: Image Upload Route Bypasses Agent Permission Check — Incomplete Fix for File Upload Authorization

Medium · published June 25, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
24.2
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00324 · 24.2th percentile
Weakness
CWE-862 · Missing Authorization
Published
2026-06-25T15:52Z
EPSS history
Timeline
  • 25 JUN 15:52Z
    LibreChat: Image Upload Route Bypasses Agent Permission Check — Incomplete Fix for File Upload Authorization
    cvelistv5