CVE-2026-18257

Improper Certificate Validation in S2OPC

Published Jul 29, 2026 CVSS 3.1 · 5.6 Medium EPSS < 1% KEV · Not listed
Description
Improper validity period check for root issuer certificate in CycloneCrypto cryptographic wrapper of S2OPC allows a certificate issued by this root issuer to be considered trusted

Remediation

Vendor Solution

Use mbedtls cryptographic wrapper of S2OPC. Or upgrade S2OPC to use CycloneCrypto wrapper of release version >= 2.0.0 or master commit >= 839ae878

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Systerel
Systerel s2opc
Vendors & Products Systerel
Systerel s2opc
Type Values Removed Values Added
Description Improper validity period check for root issuer certificate in CycloneCrypto cryptographic wrapper of S2OPC allows a certificate issued by this root issuer to be considered trusted
Title Improper Certificate Validation in S2OPC
Weaknesses CWE-295
References
Metrics cvssV3_1

{'score': 5.6, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitLab
Published
Updated
Jul 29, 2026, 6:04 PM
Reserved
Jul 29, 2026, 4:33 PM
Status
Awaiting Analysis
Published
Jul 29, 2026, 5:16 PM
Modified
Oct 24, 2026, 1:10 PM