CVE-2021-20873: Yappli

High severity, CVSS 8.1. EPSS: 0.8% chance of exploitation in the next 30 days.

Yappli is an application development platform which provides the function to access a requested URL using Custom URL Scheme. When Android apps are developed with Yappli versions since v7.3.6 and prior to v9.30.0, they are vulnerable to improper authorization in Custom URL Scheme handler, and may be directed to unintended sites via a specially crafted URL.

Affected products

• Yappli Yappli: from 7.3.6, before 9.30.0 (fixed in 9.30.0)

Published 2021-12-28. Last modified 2026-06-17.