CVE-2026-44213: OpenTelemetry.Exporter.Instana bypasses TLS certificate validation when a proxy is configured

May 8, 2026

The OpenTelemetry.Exporter.Instana NuGet package does not validate HTTPS/TLS certificates are valid when sending telemetry to a configured Instana back-end when a proxy is configured using the INSTANA_ENDPOINT_PROXY environment variable.

If a network attacker can Man-in-the-Middle (MitM) the proxy connection, all OpenTelemetry telemetry data and the Instana API key are exposed to the attacker.

References

github.com/advisories/GHSA-wfr5-454p-mjc2
github.com/open-telemetry/opentelemetry-dotnet-contrib
github.com/open-telemetry/opentelemetry-dotnet-contrib/security/advisories/GHSA-wfr5-454p-mjc2
nvd.nist.gov/vuln/detail/CVE-2026-44213

Code Behaviors & Features

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