epa4all-client is the Java Client for epa4all / ePA 3.0 in the Telematik Infrastruktur. Prior to 1.2.1, in SignedPublicKeysTrustValidatorImpl.isTrusted(), the ECDSA signature verification at line 45 discards the boolean return value of Signature.verify(). The method performs certificate chain validation, OCSP check, and signature algorithm setup, but never checks whether the signature actually matches. For any structurally valid signature, it returns true. This vulnerability is fixed in 1.2.1.

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-g8r3-5hwf-qp96 epa4all-client has a VAU Signature bypass
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Thu, 28 May 2026 16:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Wed, 27 May 2026 10:30:00 +0000

Type Values Removed Values Added
First Time appeared Com.oviva.telematik
Com.oviva.telematik epa4all-client
Oviva-ag
Oviva-ag epa4all-client
Vendors & Products Com.oviva.telematik
Com.oviva.telematik epa4all-client
Oviva-ag
Oviva-ag epa4all-client

Tue, 26 May 2026 21:45:00 +0000

Type Values Removed Values Added
Description epa4all-client is the Java Client for epa4all / ePA 3.0 in the Telematik Infrastruktur. Prior to 1.2.1, in SignedPublicKeysTrustValidatorImpl.isTrusted(), the ECDSA signature verification at line 45 discards the boolean return value of Signature.verify(). The method performs certificate chain validation, OCSP check, and signature algorithm setup, but never checks whether the signature actually matches. For any structurally valid signature, it returns true. This vulnerability is fixed in 1.2.1.
Title epa4all-client: VAU Signature bypass
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 8.1, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}


Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-05-28T14:12:28.907Z

Reserved: 2026-05-07T21:50:33.546Z

Link: CVE-2026-44900

cve-icon Vulnrichment

Updated: 2026-05-28T14:12:25.731Z

cve-icon NVD

Status : Deferred

Published: 2026-05-26T22:16:42.873

Modified: 2026-05-27T19:41:21.417

Link: CVE-2026-44900

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-05-27T10:08:22Z

Weaknesses