CVE-2026-44213: Open-Telemetry Opentelemetry-Dotnet-Contrib

Medium severity, CVSS 6.5. EPSS: 0.2% chance of exploitation in the next 30 days.

The OpenTelemetry.Exporter.Instana exports telemetry to Instana backend. Prior to 1.1.0, 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. This vulnerability is fixed in 1.1.0.

Affected products

• Open-Telemetry Opentelemetry-Dotnet-Contrib: before 1.1.0 (fixed in 1.1.0)

Published 2026-05-26. Last modified 2026-07-24.