How severe is CVE-2021-20777?

CVE-2021-20777 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2021-20777 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-20777?

CVE-2021-20777 affects Gu-global Gu. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-20777?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-20777 published?

CVE-2021-20777 was published on 2021-07-07 and last updated on 2026-06-17.

CVE-2021-20777

CVE-2021-20777 is a medium-severity vulnerability in Gu-global Gu with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-862.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
CVSS v2: 4.3
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-862
Affected product: Gu-global Gu
Published: 2021-07-07
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-20777?: 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.
How severe is CVE-2021-20777?: CVE-2021-20777 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2021-20777 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-20777?: CVE-2021-20777 affects Gu-global Gu. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-20777?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-20777 published?: CVE-2021-20777 was published on 2021-07-07 and last updated on 2026-06-17.

References

https://jvn.jp/en/jp/JVN25850723/index.html

Affected products (1)

cpe:2.3:a:gu-global:gu:*:*:*:*:*:android:*:*

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