CVE-2026-18257

mediumCVSS 5.6covered by 1 sourcefirst seen 2026-07-29

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

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Exploitation outlook

Low exploitation risk0.10% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 1% of all EPSS-scored CVEs.

Advisory coverage (1)

mediumCVE-2026-18257: Improper validity period check for root issuer certificate in CycloneCrypto cryptographic wrap…nvd · 2026-07-29

External references

NVD record for CVE-2026-18257

CVE.org record

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