CVE-2021-20777

Name: CVE-2021-20777
Creator: NVD / NIST
Published: 2021-07-07T08:15:07.887+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.3/10EPSS 0.87%

Last modified Jun 17, 2026

CVE-2021-20777 is a medium-severity vulnerability rated 4.3/10 on the CVSS scale. Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 allows a remote attacker to lead a user to access an arbitrary website via the vulnerable App.. EPSS estimates a 0.87% chance of exploitation in the next 30 days.

Description

Improper authorization in handler for custom URL scheme vulnerability in GU App for Android versions from 4.8.0 to 5.0.2 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:N/I:L/A:N

EPSS Probability

0.87%

54.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-862

Affected Software

Vendor	Product	Versions
Gu-Global	Gu	>= 4.8.0, <= 5.0.2

References

https://jvn.jp/en/jp/JVN25850723/index.htmlThird Party Advisory
https://jvn.jp/en/jp/JVN25850723/index.htmlThird Party Advisory

Timeline

Published: Jul 7, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20777?

How severe is CVE-2021-20777?

CVE-2021-20777 has a CVSS score of 4.3/10 (MEDIUM severity). The EPSS model estimates a 0.87% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20777?

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-2021-20777?

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

Scan your code now

Source: NVD / NIST