CVE-2021-20747

Name: CVE-2021-20747
Creator: NVD / NIST
Published: 2021-07-14T02:15:07.443+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 1.00%

Last modified Jun 17, 2026

CVE-2021-20747 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. 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.. EPSS estimates a 1.00% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

4.3/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

EPSS Probability

1.00%

58.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-862

Affected Software

Vendor	Product	Versions
Retty	Retty	< 4.8.13
Retty	Retty	< 4.11.14

References

https://drive.google.com/file/d/1PBYqIsK8QxEEhGJ4SEgpY7iZw3RTTDho/viewThird Party Advisory
https://jvn.jp/en/jp/JVN26891339/index.htmlThird Party Advisory
https://drive.google.com/file/d/1PBYqIsK8QxEEhGJ4SEgpY7iZw3RTTDho/viewThird Party Advisory
https://jvn.jp/en/jp/JVN26891339/index.htmlThird Party Advisory

Timeline

Published: Jul 14, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20747?

How severe is CVE-2021-20747?

CVE-2021-20747 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 1.00% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20747?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20747?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST