open-telemetry opentelemetry-dotnet up to 1.15.1 OpenTelemetry Protocol memory allocation

Summaryinfo

A vulnerability identified as problematic has been detected in open-telemetry opentelemetry-dotnet up to 1.15.1. The impacted element is an unknown function of the component OpenTelemetry Protocol Handler. This manipulation causes memory allocation. The identification of this vulnerability is CVE-2026-40182. The attack needs to be done within the local network. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in open-telemetry opentelemetry-dotnet up to 1.15.1. It has been declared as problematic. Affected by this vulnerability is some unknown functionality of the component OpenTelemetry Protocol Handler. The manipulation with an unknown input leads to a memory allocation vulnerability. The CWE definition for the vulnerability is CWE-789. The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated. As an impact it is known to affect availability. The summary by CVE is:

OpenTelemetry dotnet is a dotnet telemetry framework. From 1.13.1 to before 1.15.2, When exporting telemetry to a back-end/collector over gRPC or HTTP using OpenTelemetry Protocol format (OTLP), if the request results in a unsuccessful request (i.e. HTTP 4xx or 5xx), the response is read into memory with no upper-bound on the number of bytes consumed. This could cause memory exhaustion in the consuming application if the configured back-end/collector endpoint is attacker-controlled (or a network attacker can MitM the connection) and an extremely large body is returned by the response. This vulnerability is fixed in 1.15.2.

It is possible to read the advisory at github.com. This vulnerability is known as CVE-2026-40182 since 04/09/2026. The exploitation appears to be difficult. The attack can only be initiated within the local network. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.15.2 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Vendor

• open-telemetry

Name

• opentelemetry-dotnet

Version

• 1.15.0
• 1.15.1

Website

• Product: https://github.com/open-telemetry/opentelemetry-dotnet/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion