Vulnerability Details : CVE-2021-3827
A flaw was found in keycloak, where the default ECP binding flow allows other authentication flows to be bypassed. By exploiting this behavior, an attacker can bypass the MFA authentication by sending a SOAP request with an AuthnRequest and Authorization header with the user's credentials. The highest threat from this vulnerability is to confidentiality and integrity.
Vulnerability category: BypassGain privilege
Exploit prediction scoring system (EPSS) score for CVE-2021-3827
Probability of exploitation activity in the next 30 days: 0.11%
Percentile, the proportion of vulnerabilities that are scored at or less: ~ 44 % EPSS Score History EPSS FAQ
CVSS scores for CVE-2021-3827
Base Score | Base Severity | CVSS Vector | Exploitability Score | Impact Score | Source |
---|---|---|---|---|---|
6.8
|
MEDIUM | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N |
1.6
|
5.2
|
nvd@nist.gov |
CWE ids for CVE-2021-3827
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When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.Assigned by:
- nvd@nist.gov (Primary)
- secalert@redhat.com (Secondary)
References for CVE-2021-3827
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https://github.com/keycloak/keycloak/security/advisories/GHSA-4pc7-vqv5-5r3v
ECP SAML binding bypasses authentication flows · Advisory · keycloak/keycloak · GitHubThird Party Advisory
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https://github.com/keycloak/keycloak/commit/44000caaf5051d7f218d1ad79573bd3d175cad0d
KEYCLOAK-19177 Disable ECP flow by default for all Saml clients; ecp … · keycloak/keycloak@44000ca · GitHubPatch;Third Party Advisory
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https://access.redhat.com/security/cve/CVE-2021-3827
CVE-2021-3827- Red Hat Customer PortalVendor Advisory
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https://bugzilla.redhat.com/show_bug.cgi?id=2007512
2007512 – (CVE-2021-3827) CVE-2021-3827 keycloak-server-spi-private: ECP SAML binding bypasses authentication flowsIssue Tracking;Vendor Advisory
Products affected by CVE-2021-3827
- cpe:2.3:a:redhat:keycloak:*:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.8:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:openshift_container_platform:4.9:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:single_sign-on:7.0:*:*:*:*:*:*:*
- cpe:2.3:a:redhat:single_sign-on:7.5.0:*:*:*:*:*:*:*