Single Sign On

A flaw was found in the Dynamic Client Registration (DCR) component of Keycloak, an identity and access management solution. The default DCR policy fails to properly validate the claim path for User Property mappers, allowing them to write values to sensitive internal claim locations. An attacker with a standard user account and a limited Initial Access Token can exploit this to forge administrative roles in their access token. This allows the attacker to take over other clients, steal confidential secrets, and potentially gain full administrative control over the realm.Show less

A flaw was found in Keycloak's Authorization Services. The component responsible for matching request paths to security policies (PathMatcher) does not properly normalize URIs before comparison. By adding extra characters like a trailing slash or matrix parameters to a URL, an attacker can trick the system into applying a less restrictive security policy than intended. This allows an authenticated user to access administrative or restricted areas they should not have permission to see.Show less

Keycloak provides a mechanism called Client Policies to enforce security requirements on clients, such as requiring them to use signed JWTs for authentication. A flaw was discovered where this enforcement can be bypassed. An attacker with valid client credentials can provide a fake, unsigned assertion header that tricks the system into thinking the policy requirements have been met. This allows the attacker to authenticate using simpler methods like a client secret even when the administrator has mandated more secure, signed assertions.Show less

A flaw was found in the group search functionality of the Keycloak server's administrative API. When Fine-Grained Admin Permissions (FGAP) v2 is enabled, a delegated administrator can bypass access restrictions to view parent groups they are not authorized to see. By searching for a child group they have permission to view, the system incorrectly returns the full details of the parent group in the response, leading to the disclosure of sensitive group attributes and configuration.Show less

A flaw was found in Undertow. When Undertow receives an HTTP request where the first header line starts with one or more spaces, it incorrectly processes the request by stripping these leading spaces. This behavior, which violates HTTP standards, can be exploited by a remote attacker to perform request smuggling. Request smuggling allows an attacker to bypass security mechanisms, access restricted information, or manipulate web caches, potentially leading to unauthorized actions or data exposure.Show less

A flaw was found in Undertow. This vulnerability allows a remote attacker to construct specially crafted requests where header names are parsed differently by Undertow compared to upstream proxies. This discrepancy in header interpretation can be exploited to launch request smuggling attacks, potentially bypassing security controls and accessing unauthorized resources.Show less

A flaw was found in Undertow. A remote attacker can exploit this vulnerability by sending `\r\r\r` as a header block terminator. This can be used for request smuggling with certain proxy servers, such as older versions of Apache Traffic Server and Google Cloud Classic Application Load Balancer, potentially leading to unauthorized access or manipulation of web requests.Show less

A flaw was found in Keycloak. An administrator with `manage-clients` permission can exploit a misconfiguration where this permission is equivalent to `manage-permissions`. This allows the administrator to escalate privileges and gain control over roles, users, or other administrative functions within the realm. This privilege escalation can occur when admin permissions are enabled at the realm level.Show less

A flaw was found in Keycloak. An authenticated attacker can perform Server-Side Request Forgery (SSRF) by manipulating the `client_session_host` parameter during refresh token requests. This occurs when a Keycloak client is configured to use the `backchannel.logout.url` with the `application.session.host` placeholder. Successful exploitation allows the attacker to make HTTP requests from the Keycloak server’s network context, potentially probing internal networks or internal APIs, leading to information disclosure.Show less

Rejected reason: The Undertow web server enforces a default maximum HTTP request entity size limit. Any request (including GET or HEAD) containing a body that exceeds this configurable limit is safely dropped by the server, preventing single-request Resource Exhaustion (Out of Memory) Denial of Service attacks.Show less

A flaw was identified in Keycloak, an identity and access management solution, where it improperly follows HTTP redirects when processing certain client configuration requests. This behavior allows an attacker to trick the server into making unintended requests to internal or restricted resources. As a result, sensitive internal services such as cloud metadata endpoints could be accessed. This issue may lead to information disclosure and enable attackers to map internal network infrastructure.Show less

A security flaw in the IdentityBrokerService.performLogin endpoint of Keycloak allows authentication to proceed using an Identity Provider (IdP) even after it has been disabled by an administrator. An attacker who knows the IdP alias can reuse a previously generated login request to bypass the administrative restriction. This undermines access control enforcement and may allow unauthorized authentication through a disabled external provider.Show less

A flaw was found in the Undertow HTTP server core, which is used in WildFly, JBoss EAP, and other Java applications. The Undertow library fails to properly validate the Host header in incoming HTTP requests.As a result, requests containing malformed or malicious Host headers are processed without rejection, enabling attackers to poison caches, perform internal network scans, or hijack user sessions.Show less

A flaw was found in Undertow where malformed client requests can trigger server-side stream resets without triggering abuse counters. This issue, referred to as the "MadeYouReset" attack, allows malicious clients to induce excessive server workload by repeatedly causing server-side stream aborts. While not a protocol bug, this highlights a common implementation weakness that can be exploited to cause a denial of service (DoS).Show less

A flaw was found in hibernate-validator's 'isValid' method in the org.hibernate.validator.internal.constraintvalidators.hv.SafeHtmlValidator class, which can be bypassed by omitting the tag ending in a less-than character. Browsers may render an invalid html, allowing HTML injection or Cross-Site-Scripting (XSS) attacks.Show less

A misconfiguration flaw was found in Keycloak. This issue can allow an attacker to redirect users to an arbitrary URL if a 'Valid Redirect URI' is set to http://localhost or http://127.0.0.1, enabling sensitive information such as authorization codes to be exposed to the attacker, potentially leading to session hijacking.Show less

A denial of service vulnerability was found in keycloak where the amount of attributes per object is not limited,an attacker by sending repeated HTTP requests could cause a resource exhaustion when the application send back rows with long attribute values.Show less

A session fixation issue was discovered in the SAML adapters provided by Keycloak. The session ID and JSESSIONID cookie are not changed at login time, even when the turnOffChangeSessionIdOnLogin option is configured. This flaw allows an attacker who hijacks the current session before authentication to trigger session fixation.Show less

A vulnerability was found in Keycloak. This flaw allows attackers to bypass brute force protection by exploiting the timing of login attempts. By initiating multiple login requests simultaneously, attackers can exceed the configured limits for failed attempts before the system locks them out. This timing loophole enables attackers to make more guesses at passwords than intended, potentially compromising account security on affected systems.Show less

A vulnerability was found in Undertow where the ProxyProtocolReadListener reuses the same StringBuilder instance across multiple requests. This issue occurs when the parseProxyProtocolV1 method processes multiple requests on the same HTTP connection. As a result, different requests may share the same StringBuilder instance, potentially leading to information leakage between requests or responses. In some cases, a value from a previous request or response may be erroneously reused, which could lead to unintended data exposure. This issue primarily results in errors and connection termination but creates a risk of data leakage in multi-request environments.Show less