CVE-2026-54027Public exploitNetwork attack vector

Authenticated file injection via unchecked image upload

Published Jun 25, 2026 · Updated Jun 25, 2026

Missing authorization in LibreChat before 0.8.4-rc1 allows remote authenticated users to inject files into another agent's resources. The POST /api/files/images route passes attacker-controlled agent_id and tool_resource values to processAgentFileUpload without checking ownership or EDIT permission. Any account can therefore alter another user's agent context, execute_code, or file_search resources without access to that agent.

CVSS severity6.5
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authorization in LibreChat before 0.8.4-rc1 allows remote authenticated users to inject files into another agent's resources. The POST /api/files/images route passes attacker-controlled agent_id and tool_resource values to processAgentFileUpload without checking ownership or EDIT permission. Any account can therefore alter another user's agent context, execute_code, or file_search resources without access to that agent.

The record

CVE
CVE-2026-54027
Published
Jun 25, 2026
Updated
Jun 25, 2026
Vendor
Danny Avila
Product
LibreChat
Classifications
CWE-862, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jun 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jun 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.8.4-rc1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Danny Avila · LibreChatversion=< 0.8.4-rc1

Published CVSS scores

6.5GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-862Missing Authorization
T1190Exploit Public-Facing Application

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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