Auth bypass in Yappli

CVE-2021-20873

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.

Vulnerability class: Broken Access Control

EPSS: 0.008 (54.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-20873?
CVE-2021-20873 is a high-severity vulnerability in Yappli, classified under Missing Authorization. CVSS score: 8.1/10. Published 2021-12-28.
How severe is CVE-2021-20873?
High severity. CVSS v3 base score is 8.1 out of 10.