How severe is CVE-2020-1727?

CVE-2020-1727 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2020-1727 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-1727?

CVE-2020-1727 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-1727?

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

When was CVE-2020-1727 published?

CVE-2020-1727 was published on 2020-06-22 and last updated on 2026-06-17.

CVE-2020-1727

CVE-2020-1727 is a medium-severity vulnerability in Redhat Keycloak with a CVSS 3.x base score of 6.4. 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 6.4)
CVSS v2: 5.5
EPSS exploit prediction: 1% (52nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Redhat Keycloak
Published: 2020-06-22
Last modified: 2026-06-17

Description

A vulnerability was found in Keycloak before 9.0.2, where every Authorization URL that points to an IDP server lacks proper input validation as it allows a wide range of characters. This flaw allows a malicious to craft deep links that introduce further attack scenarios on affected clients.

Frequently asked questions

What is CVE-2020-1727?: A vulnerability was found in Keycloak before 9.0.2, where every Authorization URL that points to an IDP server lacks proper input validation as it allows a wide range of characters. This flaw allows a malicious to craft deep links that introduce further attack scenarios on affected clients.
How severe is CVE-2020-1727?: CVE-2020-1727 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2020-1727 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (52nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-1727?: CVE-2020-1727 affects Redhat Keycloak. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-1727?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-1727 published?: CVE-2020-1727 was published on 2020-06-22 and last updated on 2026-06-17.

References

https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1727

Affected products (1)

cpe:2.3:a:redhat:keycloak:*:*:*:*:*:*:*:*

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