CVE-2021-20747

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-07-14 · updated 2026-06-17
Weakness: CWE-862

Description

Improper authorization in handler for custom URL scheme vulnerability in Retty App for Android versions prior to 4.8.13 and Retty App for iOS versions prior to 4.11.14 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.

Affected products

Retty Inc. Retty App: before 4.8.13; before 4.11.14 — fixed in 4.11.14, 4.8.13

How to fix

Upgrade to a fixed version: Retty Inc. Retty App 4.11.14, 4.8.13. Check the vendor advisory for mitigations.

References

https://drive.google.com/file/d/1PBYqIsK8QxEEhGJ4SEgpY7iZw3RTTDho/view
https://jvn.jp/en/jp/JVN26891339/index.html
https://drive.google.com/file/d/1PBYqIsK8QxEEhGJ4SEgpY7iZw3RTTDho/view
https://jvn.jp/en/jp/JVN26891339/index.html

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