OpenTelemetry dotnet: Unbounded `grpc-status-details-bin` parsing in OTLP/gRPC retry handling
Published Apr 23, 2026 · Updated Apr 23, 2026
OpenTelemetry dotnet is a dotnet telemetry framework. From 1.13.1 to before 1.15.2, When exporting telemetry over gRPC using the OpenTelemetry Protocol (OTLP), the exporter may parse a server-provided grpc-status-details-bin trailer during retry handling. Prior to the fix, a malformed trailer could encode an extremely large length-delimited protobuf field which was used directly for allocation, allowing excessive memory allocation and potential denial of service (DoS). This vulnerability is fixed in 1.15.2.
Summary
What happened
OpenTelemetry dotnet is a dotnet telemetry framework. From 1.13.1 to before 1.15.2, When exporting telemetry over gRPC using the OpenTelemetry Protocol (OTLP), the exporter may parse a server-provided grpc-status-details-bin trailer during retry handling. Prior to the fix, a malformed trailer could encode an extremely large length-delimited protobuf field which was used directly for allocation, allowing excessive memory allocation and potential denial of service (DoS). This vulnerability is fixed in 1.15.2.
The record
- CVE
- CVE-2026-40891
- Published
- Apr 23, 2026
- Updated
- Apr 23, 2026
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- Unavailable
- Attack vector
- Unavailable
- Privileges
- Unavailable
Timeline
How it unfolded
- Apr 23, 2026CVE publishedPublication date reported by the CVE source.
- Apr 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
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Published CVSS scores
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Attacks
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Public exploit references
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Technologies
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