CVE-2025-10044 in Keycloak
Summary
by MITRE • 09/05/2025
A flaw was found in Keycloak. Keycloak’s account console and other pages accept arbitrary text in the error_description query parameter. This text is directly rendered in error pages without validation or sanitization. While HTML encoding prevents XSS, an attacker can craft URLs with misleading messages (e.g., fake support phone numbers or URLs), which are displayed within the trusted Keycloak UI. This creates a phishing vector, potentially tricking users into contacting malicious actors.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 11/07/2025
CVE-2025-10044 represents a significant security vulnerability within the Keycloak identity and access management platform that directly impacts user trust and system integrity. This flaw exists in Keycloak's account console and related error handling mechanisms where the error_description query parameter is processed without proper input validation or sanitization. The vulnerability stems from the application's failure to properly handle user-supplied data in error contexts, creating a dangerous condition where malicious actors can inject deceptive content into the user interface.
The technical implementation of this vulnerability allows attackers to manipulate the error_description parameter in URLs, which are then rendered directly within Keycloak's trusted user interface without adequate security controls. This presents a classic case of insecure direct object reference combined with insufficient output encoding, where the system assumes all content from query parameters is safe for display. The vulnerability specifically affects the account console and other web pages that utilize error handling mechanisms, making it particularly dangerous as these are typically accessed by authenticated users who trust the application's interface. The absence of proper sanitization creates a pathway for attackers to inject misleading information that appears legitimate within the Keycloak environment.
The operational impact of this vulnerability extends beyond simple phishing attempts, creating a sophisticated attack vector that can be leveraged for social engineering campaigns. Users interacting with the Keycloak interface may be deceived into believing they are receiving legitimate error messages containing fraudulent contact information, which could lead to unauthorized access attempts or credential theft. The phishing potential is amplified because the malicious content appears within the trusted Keycloak UI, making it more convincing than external phishing attempts. This vulnerability directly aligns with CWE-79 (Cross-Site Scripting) and CWE-20 (Improper Input Validation) classifications, representing a dangerous combination of input handling flaws that create persistent security risks.
From a threat modeling perspective, this vulnerability enables attackers to craft highly convincing phishing URLs that can be delivered through various channels including email, social engineering, or compromised applications. The attack surface is particularly concerning given that Keycloak is widely deployed in enterprise environments where user trust is paramount. The vulnerability creates a persistent threat vector that can be exploited repeatedly without requiring additional authentication or privileges, making it particularly attractive to threat actors. Security professionals should consider this vulnerability in relation to ATT&CK technique T1566 (Phishing) and T1071.004 (Application Layer Protocol: DNS) when assessing overall security posture.
Mitigation strategies for CVE-2025-10044 should focus on implementing comprehensive input validation and output sanitization for all user-supplied parameters, particularly those used in error handling contexts. Organizations should immediately implement proper parameter validation that strips or encodes potentially dangerous content before rendering it in error messages. The solution should include comprehensive content security policy enforcement and input sanitization libraries that can handle various attack vectors. Additionally, security teams should consider implementing web application firewall rules that can detect and block suspicious parameter patterns. Regular security assessments and code reviews should specifically target error handling mechanisms to prevent similar vulnerabilities from emerging in other parts of the application. The fix should also include logging and monitoring capabilities to detect potential exploitation attempts and provide forensic evidence for incident response activities.