Vulnerability · Published Jul 29, 2026 · Assigned by GitLab
CVE-2026-18257Improper Certificate Validation in S2OPC
Medium 5.6
In plain English
A medium-severity improper certificate validation in S2OPC from Systerel. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 5% of all known vulnerabilities).
Severity (CVSS 3.1)5.6Medium
Exploit odds (30 days)0.2%top 95.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official 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
Affected products (as reported)
Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:L