CVE-2026-54029

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 63/100
Published: 2026-06-25 Modified: 2026-10-25 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Interaction Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: Low
UI: None
S: Unchanged
C: None
I: High
A: None

Description

LibreChat is an enhanced ChatGPT clone that supports multiple AI providers. Prior to 0.8.4-rc1, the DELETE /api/messages/:conversationId/:messageId endpoint allows any authenticated user to delete any other user's messages. The validateMessageReq middleware only validates that the conversationId belongs to the requesting user, but the handler calls deleteMessages({ messageId }) using only the messageId as the MongoDB filter — without adding a user constraint. An attacker provides their own valid conversationId (to pass validation) and the victim's messageId (to target deletion), resulting in permanent, irrecoverable message deletion. This vulnerability is fixed in 0.8.4-rc1.

Weakness Classification (1)

Affected Software (1)

VendorProductVersion
librechat librechat < 0.8.3

References & Advisories (1)

Bug Bounty Relevance

63 / 100
✓ Network accessible
✓ Low complexity
✓ No user interaction

CVSS Score

6.5 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

EPSS — Exploitation Probability

0.27%
Raw Score 0.002720
Percentile 19.6%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00272
2026-10-28
0.00272

Intelligence Sources

nvd ref →