What’s Vulnerable › Vulnerabilities

CVE-2021-27434

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.7% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-05-20 · updated 2026-06-17
• Weakness: CWE-200

Description

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.

Affected products

• OPC UA Products Built with the .NET Framework 4.5, 4.0, and 3.5: through 3.0.7

References

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

Get alerted when CVE-2021-27434 or the next vulnerability affects your stack