Message sending and file exfiltration via unauthenticated API
Published Jul 20, 2026 · Updated Jul 20, 2026
Missing authentication in WhatsApp MCP Server before 0.2.1 allows local users to send messages and exfiltrate readable files. The loopback whatsapp-bridge /api/send endpoint accepts requests without authentication or Host validation and reads absolute media_path values without restricting them to a safe directory. Same-user processes can abuse the paired account directly, while remote attackers require a visited webpage and DNS rebinding to reach the loopback API.
Summary
What happened
Missing authentication in WhatsApp MCP Server before 0.2.1 allows local users to send messages and exfiltrate readable files. The loopback whatsapp-bridge /api/send endpoint accepts requests without authentication or Host validation and reads absolute media_path values without restricting them to a safe directory. Same-user processes can abuse the paired account directly, while remote attackers require a visited webpage and DNS rebinding to reach the loopback API.
The record
- CVE
- CVE-2026-46555
- Published
- Jul 20, 2026
- Updated
- Jul 20, 2026
- Vendor
- Very Good Plugins
- Product
- WhatsApp MCP Server
- Classifications
- CWE-346, CWE-306, CWE-22, T1567
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 20, 2026CVE publishedPublication date reported by the CVE source.
- Jul 20, 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.
- Affected versionversion=< 0.2.1
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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