CVE-2021-3637 Allocation of resources without limits or throttling in keycloak-model-infinispan

What is CVE-2021-3637?

CVE-2021-3637 is a high-severity denial of service vulnerability in Redhat Keycloak, published on 9 Jul 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A flaw was found in keycloak-model-infinispan in keycloak versions before 14.0.0 where authenticationSessions map in RootAuthenticationSessionEntity grows boundlessly which could lead to a DoS attack.

Weakness: CWE-770

Which versions are affected by CVE-2021-3637?

2 open source packages ship an affected version, including org.keycloak:keycloak-model-infinispan. It affects 2 products.

Products include Redhat Keycloak, Redhat Single Sign-On.

How do I fix CVE-2021-3637?

Upgrade org.keycloak:keycloak-model-infinispan to 14.0.0 or later.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2021-3637 being exploited?

There is no known exploitation of CVE-2021-3637 in the wild and no public exploit code.

Other vulnerabilities in Redhat Keycloak

• CVE-2022-4361 Keycloak vulnerable to cross-site scripting when validating URI-schemes on SAML and OIDC Critical 10.0
• CVE-2022-1245 Keycloak vulnerable to privilege escalation on Token Exchange feature Critical 9.8
• CVE-2021-20195 keycloak Self Stored Cross-site Scripting vulnerability Critical 9.6
• CVE-2019-14910 Keycloak Authentication Error Critical 9.3
• CVE-2019-14909 Keycloak Authentication Error Critical 9.3

All Redhat Keycloak vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as GHSA-2vp8-jv5v-6qh6.