A critical denial of service vulnerability (CVE-2025-46784) affects Entr'ouvert Lasso version 2.5.1. The flaw exists in the lasso_node_init_from_message_with_format function, where processing a specially crafted SAML response can cause memory depletion, leading to denial of service. An attacker can exploit this by sending a malformed SAML response to trigger the issue.