Bug 2445988 (CVE-2026-3872)

Summary: CVE-2026-3872 keycloak: Keycloak: Information disclosure due to redirect_uri validation bypass
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: aschwart, boliveir, mposolda, pjindal, rmartinc, security-response-team, ssilvert, sthorger, vmuzikar
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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Doc Text:
A flaw was found in Keycloak. This issue allows an attacker, who controls another path on the same web server, to bypass the allowed path in redirect Uniform Resource Identifiers (URIs) that use a wildcard. A successful attack may lead to the theft of an access token, resulting in information disclosure.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Deadline: 2026-04-15   

Description OSIDB Bzimport 2026-03-10 09:20:55 UTC 
A flaw was found in Keycloak's redirect_uri validation logic. This issue may allow bypassing the allwed path in a redirect URIs that use a wilcard. A successful attack may lead to the theft of an access token if the attacker controls another path on the same web server.