CVE-2026-7504
HighCVSS 8.1Exploitation Probability (EPSS)
Low risk39th percentile - higher than 39% of all known CVEs
Summary
A flaw was found in Keycloak's URL validation logic during redirect operations. By crafting a malicious request, an attacker could bypass validation to redirect users to unauthorized URLs, potentially leading to the exposure of sensitive information within the domain or facilitating further attacks. This vulnerability specifically affects Keycloak clients configured with a wildcard (*) in the "Valid Redirect URIs" field and requires user interaction to be successfully exploited.
Risk Assessment
The risk involves the possibility of redirecting users to malicious sites, which could result in theft of credentials, sessions, or other confidential information, and enable phishing attacks within a trusted domain.
Recommendation
It is recommended to immediately update Keycloak to a patched version and avoid using wildcards in the "Valid Redirect URIs" field, opting instead for specific, allowed URLs.
Original NVD description (English source)
A flaw was found in Keycloak's URL validation logic during redirect operations. By crafting a malicious request, an attacker could bypass validation to redirect users to unauthorized URLs, potentially leading to the exposure of sensitive information within the domain or facilitating further attacks. This vulnerability specifically affects Keycloak clients configured with a wildcard (*) in the "Valid Redirect URIs" field and requires user interaction to be successfully exploited. The issue stems from a discrepancy in how Keycloak and the underlying Java URI implementation handle the user-info component of a URL. If a malicious redirect URL is constructed using multiple @ characters in the user-info section, Java's URI parser fails to extract the user-info, leaving only the raw authority field. Consequently, Keycloak's validation check fails to detect the malformed user-info, falls back to a wildcard comparison, and incorrectly permits the malicious redirect.