CVE-2026-45575: Epa4all client Epa4all-client Vulnerability

HIGH
Advisory Identifier: GHSA-gqx7-6552-67hf
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CVSS 7.4
CWE-347
Published
Advisory Summary

CVE-2026-45575 is a HIGH (CVSS 7.4) epa4all-client vulnerability (CWE-347: Improper Verification of Cryptographic Signature) affecting Epa4all client libraries in the Maven ecosystem. The issue involves epa4all-client. Remediation is available by upgrading affected packages to version 1.2.2.

CVE-2026-45575 at a Glance

CVE Identifier CVE-2026-45575
GHSA Identifier GHSA-gqx7-6552-67hf
Severity HIGH
CVSS v3.1 Base Score 7.4
CWE Classification CWE-347: Improper Verification of Cryptographic Signature
Affected Product Epa4all client
Package Ecosystem Maven
Published Date
Last Updated

Security Impact

CVSS: 7.4

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality High (C:H)
Integrity High (I:H)
Availability None (A:N)

How to Fix CVE-2026-45575

To remediate this vulnerability, upgrade all affected Epa4all client dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

com.oviva.telematik:epa4all-client fixed: 1.2.2 
<dependency>
    <groupId>com.oviva.telematik</groupId>
    <artifactId>epa4all-client</artifactId>
    <version>1.2.2</version>
</dependency>
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

mvn dependency:tree -Dincludes=com.oviva.telematik

How to Check if You Are Affected

To determine whether your Java application is affected by CVE-2026-45575, inspect your build dependencies using the Maven Dependency Plugin:

mvn dependency:tree -Dincludes=com.oviva.telematik

Analyze the terminal output to locate any version of Epa4all client in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 1.2.2), your application is affected.

Note: The mvn dependency:tree -Dincludes=com.oviva.telematik command inspects the resolved dependency graph declared in your project's POM files; it does not perform automated security scanning or inspect runtime dynamic classpaths. Always verify runtime container classpaths and shaded JARs.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-347: Improper Verification of Cryptographic Signature, where the product does not verify, or incorrectly verifies, the cryptographic signature for data. In Epa4all client, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

### Impact An attacker who can MITM the TLS connection between the client and the IDP (within the TI network) can substitute a forged discovery document. The forged document redirects u ri_puk_idp_enc and uri_puk_idp_sig to attacker-controlled URLs. The client then encrypts the SMC-B-signed challenge response to the attacker's encryption key and POSTs it to the attacker's auth endpoint. This captures the signed authentication material. ### Patches [#36](https://github.com/oviva-ag/epa4all-client/pull/36) ### Workarounds None. ### Resources - MS-OVIVA-EPA4ALL-d453c1 ### Credits [Machine Spirits](https://machinespirits.com/) ([contact@machinespirits.de](mailto:contact@machinespirits.de)) - Dr. rer. nat. Simon Weber - Dipl.-Inf. Volker Schönefeld - Chiara Fliegner

CVE-2026-45575 Affected Epa4all client Versions

1 component(s)
Fixed Versions:
1.2.2
Product / Package Ecosystem Affected Versions Fixed Version
com.oviva.telematik:epa4all-client
maven/com.oviva.telematik/epa4all-client
Maven
< 1.2.2
1.2.2

References

GitHub Advisory / Wiki ADVISORY
https://github.com/oviva-ag/epa4all-client/security/advisories/GHSA-gqx7-6552-67hf
NVD — CVE-2026-45575 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-45575
Epa4all client Source Repository REPOSITORY
https://github.com/oviva-ag/epa4all-client/pull/36
Security Fix Commit FIX COMMIT
https://github.com/oviva-ag/epa4all-client/commit/9111d6fbb939007036a7f74b2a93bb278cb5af32
Epa4all client Source Repository REPOSITORY
https://github.com/oviva-ag/epa4all-client
Epa4all client Release RELEASE
https://github.com/oviva-ag/epa4all-client/releases/tag/v1.2.2

Frequently Asked Questions

What is CVE-2026-45575?
CVE-2026-45575 is a security vulnerability in Epa4all client involving epa4all-client under CWE-347: Improper Verification of Cryptographic Signature.
Which Epa4all client versions are affected?
Affected versions include releases prior to 1.2.2 across affected packages: com.oviva.telematik:epa4all-client.
What version fixes CVE-2026-45575?
Upgrading to 1.2.2 (or the latest patched release for your respective branch) resolves the vulnerability.
Is epa4all-client affected?
Yes, com.oviva.telematik:epa4all-client is affected in releases prior to 1.2.2. Upgrade your dependency to 1.2.2 or later.
What is the CVSS score of CVE-2026-45575?
CVE-2026-45575 has a CVSS v3.1 base score of 7.4 (HIGH) with vector string CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N.
What CWE is associated with CVE-2026-45575?
CVE-2026-45575 is classified under CWE-347: Improper Verification of Cryptographic Signature (The product does not verify, or incorrectly verifies, the cryptographic signature for data.).
How can I check Maven dependencies for CVE-2026-45575?
Run the dependency tree command: 'mvn dependency:tree -Dincludes=com.oviva.telematik'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-gqx7-6552-67hf",
  "modified" : "2026-06-08T23:31:26Z",
  "published" : "2026-05-15T18:30:48Z",
  "aliases" : [ "CVE-2026-45575" ],
  "summary" : "Improper Verification of Cryptographic Signature in com.oviva.telematik:epa4all-client",
  "details" : "### Impact\nAn attacker who can MITM the TLS connection between the client and the IDP (within the TI network) can substitute a forged discovery document. The forged document redirects u ri_puk_idp_enc and uri_puk_idp_sig to attacker-controlled URLs. The client then encrypts the SMC-B-signed challenge response to the attacker's encryption key and POSTs it to the attacker's auth endpoint. This captures the signed authentication material.\n\n### Patches\n[#36](https://github.com/oviva-ag/epa4all-client/pull/36)\n\n### Workarounds\nNone.\n\n### Resources\n- MS-OVIVA-EPA4ALL-d453c1\n\n### Credits\n[Machine Spirits](https://machinespirits.com/) ([contact@machinespirits.de](mailto:contact@machinespirits.de))\n\n- Dr. rer. nat. Simon Weber\n- Dipl.-Inf. Volker Schönefeld\n- Chiara Fliegner",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Maven",
      "name" : "com.oviva.telematik:epa4all-client"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "1.2.2"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/oviva-ag/epa4all-client/security/advisories/GHSA-gqx7-6552-67hf"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-45575"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/oviva-ag/epa4all-client/pull/36"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/oviva-ag/epa4all-client/commit/9111d6fbb939007036a7f74b2a93bb278cb5af32"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/oviva-ag/epa4all-client"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/oviva-ag/epa4all-client/releases/tag/v1.2.2"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-347" ],
    "severity" : "HIGH",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-15T18:30:48Z",
    "nvd_published_at" : "2026-05-26T21:16:40Z"
  }
}