TI-2026-32775 Aliases CVE-2026-44900 GHSA-g8r3-5hwf-qp96

epa4all-client: VAU Signature bypass

LOW 36CWE-295Published 2026-05-26 · Updated 2026-05-28

Key facts

Attack vector: Adjacent network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Spoofing
Confidentiality · integrity · availability: High · High · None
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-295.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00121 1st percentileScored 2026-11-07

Fix Fixed epa4all-client (oviva-ag): 1.2.1epa4all-client (com.oviva.telematik): 1.2.1+1 more product

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: None
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
oviva-ag	epa4all-client	before 1.2.1	1.2.1	Patch available	CNA
com.oviva.telematik	epa4all-client	before 1.2.1	1.2.1	Patch available	CNA
—	com.oviva.telematik:epa4all-client (Maven)	before 1.2.1	1.2.1	Patch available	GHSA-g8r3-5hwf-qp96

epa4all-client Vendoroviva-ag Affected before 1.2.1 Fixed in 1.2.1 Patch available CNA
epa4all-client Vendorcom.oviva.telematik Affected before 1.2.1 Fixed in 1.2.1 Patch available CNA
com.oviva.telematik:epa4all-client (Maven) Vendor— Affected before 1.2.1 Fixed in 1.2.1 Patch available GHSA-g8r3-5hwf-qp96

Remediation

Fix · CNA epa4all-client (oviva-ag) Fixed in 1.2.1
Fix · CNA epa4all-client (com.oviva.telematik) Fixed in 1.2.1
Fix · GHSA-g8r3-5hwf-qp96 com.oviva.telematik:epa4all-client (Maven) Fixed in 1.2.1 Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2026-44900
2026-10-03 Alias added: GHSA-g8r3-5hwf-qp96

References

Advisory 1

https://nvd.nist.gov/vuln/detail/CVE-2026-44900

Other 4

TI-2026-33323 epa4all-client: TLS Certificate Validation Disabled in Production CVSS 3.1HIGH 8.1
TI-2026-33324 epa4all-client: Improper Verification of Cryptographic Signature CVSS 3.1HIGH 7.4
TI-2026-35179 epa4all-client: Unauthenticated REST API for Patient Record Writes CVSS 3.1MEDIUM 6.5

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences