CVE-2026-44900
ECDSA Signature Verification Bypass in epa4all-client
Publication date: 2026-05-26
Last updated on: 2026-05-26
Assigner: GitHub, Inc.
Description
Description
CVSS Scores
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Meta Information
Affected Vendors & Products
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-295 | The product does not validate, or incorrectly validates, a certificate. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
The vulnerability exists in the epa4all-client Java Client for epa4all / ePA 3.0. Specifically, before version 1.2.1, the method SignedPublicKeysTrustValidatorImpl.isTrusted() incorrectly handles ECDSA signature verification. Although it performs certificate chain validation, OCSP checks, and signature algorithm setup, it ignores the actual result of the signature verification (Signature.verify()). As a result, any structurally valid signature is accepted as trusted, even if it does not match correctly.
How can this vulnerability impact me? :
This vulnerability can lead to a critical security risk because it allows an attacker to bypass proper signature verification. Since any structurally valid signature is accepted, an attacker could potentially present forged or invalid signatures that are treated as trusted. This compromises the integrity and authenticity of communications or data validated by the epa4all-client, potentially leading to unauthorized access or data manipulation.
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, upgrade the epa4all-client to version 1.2.1 or later, where the issue with signature verification in SignedPublicKeysTrustValidatorImpl.isTrusted() has been fixed.