CVE-2020-1727

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-06-22 · updated 2026-06-17
Weakness: CWE-20

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.

Affected products

Keycloak: before 9.0.2 — fixed in 9.0.2

How to fix

Upgrade to a fixed version: Keycloak 9.0.2. Check the vendor advisory for mitigations.

References

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

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