CVE-2026-40891

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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector ADJACENT_NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/open-telemetry/opentelemetry-dotnet/pull/5980	Issue Tracking Patch
https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064	Issue Tracking Patch
https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-mr8r-92fq-pj8p	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:opentelemetry:opentelemetry:*:*:*:*:*:.net:*:*

History

No history.

Information

Published : 2026-04-23 18:16

Updated : 2026-06-17 10:45

NVD link : CVE-2026-40891

Mitre link : CVE-2026-40891

CVE.ORG link : CVE-2026-40891

JSON object : View

Products Affected

opentelemetry

opentelemetry

CWE

CWE-789

Memory Allocation with Excessive Size Value

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