CVE-2026-44900
epa4all-client: VAU Signature bypass
CVSS Score
8.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-295 |
| Vendor | oviva-ag |
| Product | epa4all-client |
| Published | May 26, 2026 |
| Last Updated | May 28, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N Attack Vector
Adjacent
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Affected Versions
oviva-ag / epa4all-client
< 1.2.1
com.oviva.telematik / epa4all-client
< 1.2.1