Telemetry and API-key disclosure via disabled TLS validation
Published May 26, 2026 · Updated May 26, 2026
Improper certificate validation in OpenTelemetry.Exporter.Instana before 1.1.0 allows man-in-the-middle attackers to read telemetry and API keys. Transport.ConfigureBackendClient creates an HttpClient whose handler accepts any server certificate whenever INSTANA_ENDPOINT_PROXY contains a valid proxy URL. Exploitation requires an attacker-controlled or interceptable proxy connection, exposing all exported telemetry and the service's Instana API key without necessarily interrupting delivery.
Summary
What happened
Improper certificate validation in OpenTelemetry.Exporter.Instana before 1.1.0 allows man-in-the-middle attackers to read telemetry and API keys. Transport.ConfigureBackendClient creates an HttpClient whose handler accepts any server certificate whenever INSTANA_ENDPOINT_PROXY contains a valid proxy URL. Exploitation requires an attacker-controlled or interceptable proxy connection, exposing all exported telemetry and the service's Instana API key without necessarily interrupting delivery.
The record
- CVE
- CVE-2026-44213
- Published
- May 26, 2026
- Updated
- May 26, 2026
- Vendor
- OpenTelemetry
- Product
- OpenTelemetry .NET Contrib
- Classifications
- CWE-295, T1557
- Attack vector
- network
- Privileges
- Unavailable
Timeline
How it unfolded
- May 26, 2026CVE publishedPublication date reported by the CVE source.
- May 26, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=< 1.1.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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