Quick answers
- Is CVE-2026-9758 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-9758 being exploited in the wild.
- How severe is CVE-2026-9758?
- High severity, with a CVSS score of 7.3, published 10 June 2026.
- Which products and versions are affected?
- Systerel S2OPC 1.5.0 and later.
- Is there a fix for CVE-2026-9758?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-9758 attacked?
- It is attacked over the network, in a software library.
- Am I affected by CVE-2026-9758?
- Check whether you run Systerel S2OPC at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
A vulnerability exists in the S2OPC certificate validation process, specifically within the Trust List Check step. The root cause is an incorrect length parameter used in a memcmp() operation within both the MbedTLS and CycloneCrypto wrappers. Instead of comparing the full length of the certificate, the code only compares the number of bytes corresponding to the subject length. An attacker can exploit this by crafting a certificate with the same subject name, total length, and serial number as a trusted certificate, even if the public keys differ. This allows an untrusted certificate to be accepted as trusted, enabling unauthorized network access without authentication.
Affected products
- Systerel S2OPC 1.5.0 and later
Timeline
- 2026-06-10: advisory: NVD and GitLab advisory published