CVE-2026-44213
MEDIUMCVE-2026-44213 is a medium-severity (CVSS 6.5) CWE-295 vulnerability in OpenTelemetry.Exporter.Instana. O3 Security confirms whether CVE-2026-44213 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
OpenTelemetry.Exporter.Instana bypasses TLS certificate validation when a proxy is configured
Real-World Exposure
OpenTelemetry.Exporter.InstanaReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects NuGet packages — download data is not available via public APIs for these ecosystems.
Description
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 Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| .NETNuGet | OpenTelemetry.Exporter.Instana | all versions | 1.1.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for OpenTelemetry.Exporter.Instana. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update OpenTelemetry.Exporter.Instana to 1.1.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-44213 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-44213 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-44213. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-44213 in your dependencies?
O3 detects CVE-2026-44213 across NuGet dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.