CVE-2026-18257: CWE-295: Improper Certificate Validation in Systerel S2OPC
CVE-2026-18257 is a medium severity vulnerability in Systerel's S2OPC version 1.5.0. It involves improper validation of the validity period for the root issuer certificate within the CycloneCrypto cryptographic wrapper. This flaw can cause certificates issued by the affected root issuer to be incorrectly trusted.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-18257) in Systerel S2OPC version 1.5.0 arises from an improper validity period check for the root issuer certificate in the CycloneCrypto cryptographic wrapper. Due to this improper validation, certificates issued by this root issuer may be erroneously accepted as trusted, potentially undermining the certificate trust model.
Potential Impact
The improper certificate validation can lead to acceptance of certificates that should not be trusted, potentially allowing an attacker to impersonate entities or intercept communications. The CVSS 3.1 base score is 5.6 (medium), reflecting network attack vector, high attack complexity, no privileges required, no user interaction, and impacts on confidentiality, integrity, and availability at a low level.
Mitigation Recommendations
No official patch or remediation is currently available for this vulnerability. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is released, users should consider additional certificate validation controls or restrict trust to known good certificates where possible.
CVE-2026-18257: CWE-295: Improper Certificate Validation in Systerel S2OPC
Description
CVE-2026-18257 is a medium severity vulnerability in Systerel's S2OPC version 1.5.0. It involves improper validation of the validity period for the root issuer certificate within the CycloneCrypto cryptographic wrapper. This flaw can cause certificates issued by the affected root issuer to be incorrectly trusted.
CVSS v3.1
Score 5.6medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-18257) in Systerel S2OPC version 1.5.0 arises from an improper validity period check for the root issuer certificate in the CycloneCrypto cryptographic wrapper. Due to this improper validation, certificates issued by this root issuer may be erroneously accepted as trusted, potentially undermining the certificate trust model.
Potential Impact
The improper certificate validation can lead to acceptance of certificates that should not be trusted, potentially allowing an attacker to impersonate entities or intercept communications. The CVSS 3.1 base score is 5.6 (medium), reflecting network attack vector, high attack complexity, no privileges required, no user interaction, and impacts on confidentiality, integrity, and availability at a low level.
Mitigation Recommendations
No official patch or remediation is currently available for this vulnerability. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is released, users should consider additional certificate validation controls or restrict trust to known good certificates where possible.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitLab
- Date Reserved
- 2026-07-29T16:33:59.899Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a6a48789c2644c7f8e515a1
Added to database: 07/29/2026, 18:37:44 UTC
Last enriched: 07/29/2026, 18:52:49 UTC
Last updated: 07/29/2026, 18:52:49 UTC
Views: 3
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