CVE-2026-52723
CriticalCVSS 9.1Summary
ePA 3.x Integration before version 1.3.0 contains a vulnerability in VAU server certificate validation. A network-positioned attacker can intercept the VAU handshake and impersonate the server, controlling session keys and reading or modifying encrypted traffic.
Risk Assessment
The vulnerability allows an attacker to gain full control over communication with the ePA system, potentially compromising confidentiality and integrity of medical data.
Recommendation
It is recommended to update ePA 3.x Integration to version 1.3.0 and enable TLS certificate verification.
Original NVD description (English source)
ePA 3.x Integration implements the authorization workflow and writes Medical Information Objects to Germany's electronic patient record. Prior to 1.3.0, ePA 3.x Integration performs VAU server certificate validation in app/vau/VAUProtokoll.py without anchoring the signed_vau_server_pub_keys and AUT_VAU_CertData certificate path to independent trusted material. A network-positioned attacker between the DiGA backend and the ePA system can intercept the VAU handshake, supply attacker-controlled certificate and key material, and satisfy the circular trust relationship. Because TLS certificate verification is also disabled in affected versions, no independent server-authentication layer prevents the attack. The attacker can impersonate the VAU server, control the negotiated session keys, and read or modify all encrypted VAU traffic. This issue is fixed in version 1.3.0.