Main Vulnerability Database Vulnerabilities #VU130236

Input validation error in WhatsApp Messenger for Android and WhatsApp Messenger for iOS - CVE-2026-23866

Published: May 6, 2026

Vulnerability identifier: #VU130236

CSH Severity: High

CVSS v4: 8.5 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-23866

CWE-ID: CWE-20

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to insufficient validation of AI rich response messages for Instagram Reels. A remote attacker can force the application into processing of media content from an arbitrary URL on another user’s device, including triggering OS-controlled custom URL scheme handlers.

Affected software

WhatsApp Messenger for Android
WhatsApp Messenger for iOS

How to mitigate CVE-2026-23866

Install updates from vendor's website.

WhatsApp Messenger for Android - update to 2.26.7.10
WhatsApp Messenger for iOS - update to 26.15.72

External References

https://www.whatsapp.com/security/advisories/2026/#CVE-2026-23866

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