CVE-2021-24026

Severity: critical (CVSS 9.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-06 · updated 2026-06-17
Weakness: CWE-787

Description

A missing bounds check within the audio decoding pipeline for WhatsApp calls in WhatsApp for Android prior to v2.21.3, WhatsApp Business for Android prior to v2.21.3, WhatsApp for iOS prior to v2.21.32, and WhatsApp Business for iOS prior to v2.21.32 could have allowed an out-of-bounds write.

Affected products

Facebook WhatsApp for Android: before 2.21.3 — fixed in 2.21.3
Whatsapp Business: before 2.21.3; before 2.21.32 — fixed in 2.21.3, 2.21.32

How to fix

Upgrade to a fixed version: Facebook WhatsApp for Android 2.21.3; Whatsapp Business 2.21.3, 2.21.32. Check the vendor advisory for mitigations.

References

https://www.whatsapp.com/security/advisories/2021/
https://www.whatsapp.com/security/advisories/2021/

Get alerted when CVE-2021-24026 or the next vulnerability affects your stack