CVE & CISA-KEV Catalog

CVE-2026-4400

MEDIUM
6.5
CVSS v3
NVD

Description

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.

How to fix

Remediation Available
millie chat botNVD
Affected:< 3.6.0Fixed in:3.6.0CVE-2026-4400derived from NVD
millie chatbotNVD
Affected:< 3.6.0Fixed in:3.6.0CVE-2026-4400derived from NVD

Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.

CVSS v3 Vector

Exploitability

Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone
User InteractionNone
ScopeUnchanged

Impact

ConfidentialityHigh
IntegrityLow
AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N

Exploit Intelligence

0.21%probability of exploitation in 30 days
11thpercentile

Low risk: more likely to be exploited than 11% of all known CVEs.

References

Third-Party Advisory1

Related Vulnerabilities

Other CWE-639 (Authorization Bypass Through User-Controlled Key) vulnerabilities, ordered by exploit likelihood. View all

CVESeverityCVSSEPSSExploitedFix
CVE-2023-6875Critical9.890%--
CVE-2024-46982High7.561%-Fix
CVE-2021-45428Critical9.857%--
CVE-2019-17382Critical9.154%-Fix
CVE-2019-13360Critical9.824%--
CVE-2023-48783Medium5.422%-Fix
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Markdown

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HTML

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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-04-14.