Summary
Keycloak Untrusted Certificate Validation vulnerability
A flaw was found in keycloak-core. This flaw considers the scenario when using X509 Client Certificate Authenticatior with the option "Revalidate Client Certificate". A user may be able to choose, if directly connect to keycloak (not passing via reverse proxy) a specific certificate. If there's a configuration error in KC_SPI_TRUSTSTORE_FILE_FILE the authenticator allows even with the "Cannot validate client certificate trust: Truststore not available" message as there's no certificate to trust against.
Impact
CVE-2023-1664 has a CVSS score of 6.5 (Medium). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (21.1.2); upgrading removes the vulnerable code path.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2023-1664? CVE-2023-1664 is a medium-severity security vulnerability in org.keycloak:keycloak-core (maven), affecting versions < 21.1.2. It is fixed in 21.1.2.
- How severe is CVE-2023-1664? CVE-2023-1664 has a CVSS score of 6.5 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Which versions of org.keycloak:keycloak-core are affected by CVE-2023-1664? org.keycloak:keycloak-core (maven) versions < 21.1.2 is affected.
- Is there a fix for CVE-2023-1664? Yes. CVE-2023-1664 is fixed in 21.1.2. Upgrade to this version or later.
- Is CVE-2023-1664 exploitable, and should I be worried? Whether CVE-2023-1664 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2023-1664 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2023-1664? Upgrade
org.keycloak:keycloak-coreto 21.1.2 or later.