CVE-2021-27434

7.5 highEPSS 1.7%

High (7.5) in unified-automation .net based opc ua client\/server sdk. EPSS 1.7% chance of exploitation in the next 30 days.

Products with Unified Automation .NET based OPC UA Client/Server SDK Bundle: Versions V3.0.7 and prior (.NET 4.5, 4.0, and 3.5 Framework versions only) are vulnerable to an uncontrolled recursion, which may allow an attacker to trigger a stack overflow.

Severity

CVSS 3.1

7.5 high

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS: 1.7% chance of exploitation in the next 30 days; higher than 77% of CVEs (scores of 2026-10-31)
CWEs: CWE-674, CWE-200
Published: 2021-05-20
Modified: 2026-06-17
Record from: the NVD, synced 2026-10-19

Affected

unified-automation:.net_based_opc_ua_client\/server_sdk

References

https://us-cert.cisa.gov/ics/advisories/icsa-21-133-04
https://us-cert.cisa.gov/ics/advisories/icsa-21-133-04

Check your stack JSON