CVE-2026-40891: CVE-2026-40891: Denial of Service via Unbounded Memory Allocation in OpenTelemetry .NET gRPC Trailer Parsing

📰 Dev.to · CVE Reports

Learn about CVE-2026-40891, a Denial of Service vulnerability in OpenTelemetry .NET gRPC, and how to mitigate it

intermediate Published 23 Apr 2026

Action Steps

Identify if your system is using the vulnerable OpenTelemetry .NET gRPC version
Update to the latest version of OpenTelemetry .NET gRPC to patch the vulnerability
Configure memory allocation limits to prevent unbounded memory allocation
Monitor system resources to detect potential Denial of Service attacks
Test your system for vulnerability to CVE-2026-40891 using fuzz testing or other security testing tools

Who Needs to Know This

Developers and DevOps teams working with OpenTelemetry and gRPC should be aware of this vulnerability to ensure the security and reliability of their systems

Key Insight

💡 Unbounded memory allocation in OpenTelemetry .NET gRPC can lead to Denial of Service attacks, highlighting the importance of secure coding practices and regular security updates