CVE-2026-54027
LibreChat: Image Upload Route Bypasses Agent Permission Check — Incomplete Fix for File Upload Authorization
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.
INFO
Published Date :
June 25, 2026, 5:16 p.m.
Last Modified :
June 26, 2026, 7:02 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 | MEDIUM | [email protected] |
Solution
- Update LibreChat to version 0.8.4-rc1.
- Verify image upload permissions are enforced.
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-2026-54027.
| URL | Resource |
|---|---|
| https://github.com/danny-avila/LibreChat/security/advisories/GHSA-c55r-p24w-hcj5 | Exploit Vendor Advisory |
| https://github.com/danny-avila/LibreChat/security/advisories/GHSA-c55r-p24w-hcj5 | 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-2026-54027 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-2026-54027
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-2026-54027 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-54027 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. 26, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:librechat:librechat:*:*:*:*:*:*:*:* versions up to (including) 0.8.3 Added Reference Type GitHub, Inc.: https://github.com/danny-avila/LibreChat/security/advisories/GHSA-c55r-p24w-hcj5 Types: Exploit, Vendor Advisory Added Reference Type CISA-ADP: https://github.com/danny-avila/LibreChat/security/advisories/GHSA-c55r-p24w-hcj5 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-c55r-p24w-hcj5 Added SSVC {'id': 'CVE-2026-54027', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-06-26T15:20:33.829289Z'} -
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': '< 0.8.4-rc1'}]}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N Added CWE CWE-862 Added Reference https://github.com/danny-avila/LibreChat/security/advisories/GHSA-c55r-p24w-hcj5