GHSA-G8R3-5HWF-QP96

Vulnerability from github – Published: 2026-05-08 23:47 – Updated: 2026-05-08 23:47
VLAI
Summary
epa4all-client has a VAU Signature bypass
Details

Impact

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.

Patches

Patched in #34.

Workarounds

None.

Resources

Credits

Machine Spirits (contact@machinespirits.de) - Dr. rer. nat. Simon Weber - Dipl.-Inf. Volker Schönefeld - Chiara Fliegner

Severity
8.1 (High)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Show details on source website
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{
  "affected": [
    {
      "database_specific": {
        "last_known_affected_version_range": "\u003c= 1.2.0"
      },
      "package": {
        "ecosystem": "Maven",
        "name": "com.oviva.telematik:epa4all-client"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "1.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-44900"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-295"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-05-08T23:47:12Z",
    "nvd_published_at": null,
    "severity": "HIGH"
  },
  "details": "### Impact\nIn 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.\n\n### Patches\nPatched in [#34](https://github.com/oviva-ag/epa4all-client/pull/34).\n\n### Workarounds\nNone.\n\n### Resources\n- [MS-OVIVA-EPA4ALL-d76aec](https://www.machinespirits.com/advisory/d76aec/)\n\n### Credits\n\n[Machine Spirits](https://machinespirits.com) (contact@machinespirits.de)\n- Dr. rer. nat. Simon Weber\n- Dipl.-Inf. Volker Sch\u00f6nefeld\n- Chiara Fliegner",
  "id": "GHSA-g8r3-5hwf-qp96",
  "modified": "2026-05-08T23:47:12Z",
  "published": "2026-05-08T23:47:12Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/oviva-ag/epa4all-client/security/advisories/GHSA-g8r3-5hwf-qp96"
    },
    {
      "type": "WEB",
      "url": "https://github.com/oviva-ag/epa4all-client/pull/34"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/oviva-ag/epa4all-client"
    },
    {
      "type": "WEB",
      "url": "https://www.machinespirits.com/advisory/d76aec"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "epa4all-client has a VAU Signature bypass"
}


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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Detection rules are retrieved from Rulezet.