Package Instance

Denial of Service in Keycloak Server via Security Headers
A potential Denial of Service (DoS) vulnerability has been identified in Keycloak, which could allow an administrative user with the rights to change realm settings to disrupt the service. This is done by modifying any of the security headers and inserting newlines, which causes the Keycloak server to write to a request that is already terminated, leading to a failure of said request.

Service disruption may happen, users will be unable to access applications relying on Keycloak, or any of the consoles provided by Keycloak itself on the affected realm.

Duplicate Advisory: Keycloak vulnerable to Cleartext Transmission of Sensitive Information
# Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-g6qq-c9f9-2772. This link is maintained to preserve external references.

# Original Description
A vulnerability was found in Keycloak. The environment option `KC_CACHE_EMBEDDED_MTLS_ENABLED` does not work and the JGroups replication configuration is always used in plain text which can allow an attacker that has access to adjacent networks related to JGroups to read sensitive information.

Duplicate Advisory: Keycloak Build Process Exposes Sensitive Data
## Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-v7gv-xpgf-6395. This link is maintained to preserve external references.

## Original Description
A flaw was found in Keycloak. This issue occurs because sensitive runtime values, such as passwords, may be captured during the Keycloak build process and embedded as default values in bytecode, leading to unintended information disclosure. In Keycloak 26, sensitive data specified directly in environment variables during the build process is also stored as a default values, making it accessible during runtime. Indirect usage of environment variables for SPI options and Quarkus properties is also vulnerable due to unconditional expansion by PropertyMapper logic, capturing sensitive data as default values in all Keycloak versions up to 26.0.2.

Keycloak unable to restrict access to the admin console
A flaw was found in Keycloak. The Keycloak guides recommend to not expose /admin path to the outside in case the installation is using a proxy. The issue occurs at least via ha-proxy, as it can be tricked to using relative/non-normalized paths to access the /admin application path relative to /realms which is expected to be exposed.

Keycloak proxy header handling Denial-of-Service (DoS) vulnerability
Keycloak versions 26 and earlier are vulnerable to a denial-of-service (DoS) attack through improper handling of proxy headers. When Keycloak is configured to accept incoming proxy headers, it may accept non-IP values, such as obfuscated identifiers, without proper validation. This can lead to costly DNS resolution operations, which an attacker could exploit to tie up IO threads and potentially cause a denial of service.

The attacker must have access to send requests to a Keycloak instance that is configured to accept proxy headers, specifically when reverse proxies do not overwrite incoming headers, and Keycloak is configured to trust these headers.

For Keycloak version 26, for successful exploitation includes: the realm must have SslRequired=EXTERNAL (the default), HTTP must be enabled, the instance must not be using a full hostname URL, access must come from behind a proxy (assuming the proxy overwrites the X-Forwarded-For header), and trusted proxies must not be set or must incorrectly trust the client from which the request is originating.

Duplicate Advisory:  Keycloak allows access to admin path through flaw
### Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-j4vq-q93m-4683. This link is maintained to preserve external references.

### Original Description
A flaw was found in Keycloak. The Keycloak guides recommend to not expose /admin path to the outside in case the installation is using a proxy. The issue occurs at least via ha-proxy, as it can be tricked to using relative/non-normalized paths to access the /admin application path relative to /realms which is expected to be exposed.

Keycloak allows unrestricted admin use of system and environment variables
A security vulnerability has been identified that allows admin users to access sensitive server environment variables and system properties through user-configurable URLs. Specifically, when configuring backchannel logout URLs or admin URLs, admin users can include placeholders like ${env.VARNAME} or ${PROPNAME}. The server replaces these placeholders with the actual values of environment variables or system properties during URL processing.

Duplicate Advisory: Keycloak Path Traversal Vulnerability Due to External Control of File Name or Path
## Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-5545-r4hg-rj4m. This link is maintained to preserve external references.

## Original Description
A vulnerability was found in Keycloak. A user with high privileges could read sensitive information from a Vault file that is not within the expected context. This attacker must have previous high access to the Keycloak server in order to perform resource creation, for example, an LDAP provider configuration and set up a Vault read file, which will only inform whether that file exists or not.

Keycloak on Quarkus CLI option for encrypted JGroups ignored
The env option `KC_CACHE_EMBEDDED_MTLS_ENABLED` does not work and the jgroups replication configuration is always used in plain. This option worked before in 24 and 22. More info in public issue https://github.com/keycloak/keycloak/issues/34644.

Duplicate Advisory: Keycloak proxy header handling Denial-of-Service (DoS) vulnerability
## Duplicate Advisory
This advisory has been withdrawn because it is a duplicate of GHSA-jgwc-jh89-rpgq. This link is maintained to preserve external references.

## Original Description
A vulnerability was found in the Keycloak Server. The Keycloak Server is vulnerable to a denial of service (DoS) attack due to improper handling of proxy headers. When Keycloak is configured to accept incoming proxy headers, it may accept non-IP values, such as obfuscated identifiers, without proper validation. This issue can lead to costly DNS resolution operations, which an attacker could exploit to tie up IO threads and potentially cause a denial of service.
The attacker must have access to send requests to a Keycloak instance that is configured to accept proxy headers, specifically when reverse proxies do not overwrite incoming headers, and Keycloak is configured to trust these headers.

Keycloak has an improper input validation vulnerability
A flaw was found in Keycloak. This improper input validation vulnerability occurs because Keycloak accepts RFC-compliant matrix parameters in URL path segments, while common reverse proxy configurations may ignore or mishandle them. A remote attacker can craft requests to mask path segments, potentially bypassing proxy-level path filtering. This could expose administrative or sensitive endpoints that operators believe are not externally reachable.