CVE-2026-44900

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2026-44900
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44900.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-44900
Aliases
Published
2026-05-26T21:04:53Z
Modified
2026-08-12T16:25:17Z
Severity
  • 8.1 (High) CVSS_V3 - CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
epa4all-client: VAU Signature bypass
Details

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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
        "CWE-295"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/44xxx/CVE-2026-44900.json"
}
References

Affected packages

Git / github.com/oviva-ag/epa4all-client

Affected ranges

Type
GIT
Repo
https://github.com/oviva-ag/epa4all-client
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6
Database specific
Show details 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "1.2.1"
        }
    ],
    "source": "AFFECTED_FIELD"
}

Affected versions

epa4all-client/v0.*
epa4all-client/v0.0.2-rc.0
epa4all-client/v0.0.3-rc.0
v0.*
v0.0.4
v0.0.5
v0.0.6
v0.0.7
v0.0.8
v0.0.9
v1.*
v1.0.0
v1.0.1
v1.0.2
v1.0.3
v1.0.3-rc.2
v1.0.4-rc.1
v1.1.0
v1.1.1
v1.1.1-rc.0
v1.2.0

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-44900.json"
vanir_signatures 
[
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "181118184525831887307810226594547994740",
                "71686158905792473797514938050563979926",
                "220426661105732065751424757946103786951",
                "217835864713610173097007328788152445091",
                "271863141297825314928147573796093117875",
                "219476708332884617218025522771184397972",
                "270545454777956786985407730446358871363",
                "148001014682448145396629012250166341123",
                "114685946368072089166944777835336812171",
                "101804884370391579187844878415863945962",
                "290620666043658206325141165967195813421",
                "113733595349261336119811680451020657124",
                "242780960819741343164487702071292704996",
                "187622935415389194453841136217522995461",
                "51995103149806247417055846500732687400",
                "253768069638543364593732898853672718891",
                "321544711301458627350015494708065527455",
                "335915038979836551863709027751354944456",
                "105135349804760838859480469610730392589",
                "102715412356406950219770955940244365114"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-44900-0340d8a5",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/oviva-ag/epa4all-client/commit/e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6",
        "target": {
            "file": "vau/vau-httpclient/src/main/java/com/oviva/telematik/vau/httpclient/internal/SignedPublicKeysTrustValidatorImpl.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "152320029170772371568148515103622094065",
            "length": 717
        },
        "id": "CVE-2026-44900-299be349",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/oviva-ag/epa4all-client/commit/e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6",
        "target": {
            "file": "vau/vau-httpclient/src/main/java/com/oviva/telematik/vau/httpclient/internal/SignedPublicKeysTrustValidatorImpl.java",
            "function": "isTrusted"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "line_hashes": [
                "128105541723180769108402405937591158225",
                "244036373056257559619278424501304528004",
                "83924046338240063547189581906308206165",
                "192092695851175725203867735832647298327",
                "101265061726185422164134040250765107134",
                "124450592394235045677730040363130997696",
                "249527586736346887202759455357152332951",
                "336538503709471426103492731203160675703"
            ],
            "threshold": 0.9
        },
        "id": "CVE-2026-44900-398b6eb9",
        "signature_type": "Line",
        "signature_version": "v1",
        "source": "https://github.com/oviva-ag/epa4all-client/commit/e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6",
        "target": {
            "file": "vau/vau-httpclient/src/main/java/com/oviva/telematik/vau/httpclient/internal/SignedPublicKeysTrustValidatorFactory.java"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "154263762694756952047399939232652243851",
            "length": 118
        },
        "id": "CVE-2026-44900-44e72aaf",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/oviva-ag/epa4all-client/commit/e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6",
        "target": {
            "file": "vau/vau-httpclient/src/main/java/com/oviva/telematik/vau/httpclient/internal/SignedPublicKeysTrustValidatorFactory.java",
            "function": "create"
        }
    },
    {
        "deprecated": false,
        "digest": {
            "function_hash": "68809148766778528062299133107425454022",
            "length": 129
        },
        "id": "CVE-2026-44900-d9cfae7e",
        "signature_type": "Function",
        "signature_version": "v1",
        "source": "https://github.com/oviva-ag/epa4all-client/commit/e13fa838c7b2c7e66f9abfffbe108a85f2f4d0c6",
        "target": {
            "file": "vau/vau-httpclient/src/main/java/com/oviva/telematik/vau/httpclient/internal/SignedPublicKeysTrustValidatorImpl.java",
            "function": "SignedPublicKeysTrustValidatorImpl"
        }
    }
]
vanir_signatures_modified 
"2026-08-12T16:25:17Z"