It was found that Keycloak's SAML broker, versions up to 6.0.1, did not verify missing message signatures. If an attacker modifies the SAML Response and removes the <Signature> sections, the message is still accepted, and the message can be modified. An attacker could use this flaw to impersonate other users and gain access to sensitive information.
{
"severity": "MODERATE",
"github_reviewed": true,
"cwe_ids": [
"CWE-347"
],
"github_reviewed_at": "2019-09-19T15:26:01Z",
"nvd_published_at": "2019-08-14T17:15:00Z"
}