CVE-2026-4400

Insecure Direct Object Reference (IDOR) vulnerability in 1millionbot Millie chat that allows private conversations of other users being viewed by simply changing the conversation ID. The vulnerability is present in the endpoint 'api.1millionbot.com/api/public/conversations/' and, if exploited, could allow a remote attacker to access other users private chatbot conversations, revealing sensitive or confidential data without requiring credentials or impersonating users. In order for the vulnerability to be exploited, the attacker must have the user's conversation ID.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://www.incibe.es/en/incibe-cert/notices/aviso/multiple-vulnerabilities-1millionbot-millie-chatbot	Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:1millionbot:millie_chatbot:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-31 11:16

Updated : 2026-06-17 10:56

NVD link : CVE-2026-4400

Mitre link : CVE-2026-4400

CVE.ORG link : CVE-2026-4400

JSON object : View

Products Affected

1millionbot

millie_chatbot

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

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