open-telemetry/opentelemetry-dotnet

OpenTelemetry.Exporter.OpenTelemetryProtocol is the OTLP (OpenTelemetry Protocol) exporter implementation. From 1.8.0 to 1.15.2, the OTLP disk retry feature in OpenTelemetry.Exporter.OpenTelemetryProtocol silently fell back to Path.GetTempPath() when OTEL_DOTNET_EXPERIMENTAL_OTLP_RETRY=disk was set but OTEL_DOTNET_EXPERIMENTAL_OTLP_DISK_RETRY_DIRECTORY_PATH was not configured. The exporter stored and loaded *.blob files under fixed, signal-named subdirectories (traces, metrics, logs) beneath that shared temporary root path. On multi-user systems where the temporary directory is accessible to other local accounts, this allows an attacker to write crafted *.blob files, read *.blob files written by the application between export failures, or deposit numerous or oversized blob files, degrading retry-loop performance or consuming disk space. This vulnerability is fixed in 1.15.3.

OpenTelemetry.Exporter.Zipkin is the .NET Zipkin exporter for OpenTelemetry. In versions 1.15.2 and earlier, the Zipkin exporter remote endpoint cache accepts unbounded key growth derived from span attributes. In high-cardinality scenarios, a process using Zipkin export for client or producer spans could experience avoidable memory growth under sustained unique remote endpoint values, increasing process memory usage over time and degrading availability. This issue is fixed in version 1.15.3, which introduces a bounded, thread-safe LRU cache for remote endpoints with a fixed maximum size.

OpenTelemetry dotnet is a dotnet telemetry framework. In OpenTelemetry.Api 0.5.0-beta.2 to 1.15.2 and OpenTelemetry.Extensions.Propagators 1.3.1 to 1.15.2, The implementation details of the baggage, B3 and Jaeger processing code in the OpenTelemetry.Api and OpenTelemetry.Extensions.Propagators NuGet packages can allocate excessive memory when parsing which could create a potential denial of service (DoS) in the consuming application. This vulnerability is fixed in 1.15.3.

OpenTelemetry dotnet is a dotnet telemetry framework. In 1.6.0-rc.1 and earlier, OpenTelemetry.Exporter.Jaeger may allow sustained memory pressure when the internal pooled-list sizing grows based on a large observed span/tag set and that enlarged size is reused for subsequent allocations. Under high-cardinality or attacker-influenced telemetry input, this can increase memory consumption and potentially cause denial of service. There is no plan to fix this issue as OpenTelemetry.Exporter.Jaeger was deprecated in 2023.

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.

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.

OpenTelemetry dotnet is a dotnet telemetry framework. In affected versions of `OpenTelemetry.Instrumentation.Http` and `OpenTelemetry.Instrumentation.AspNetCore` the `url.full` writes attribute/tag on spans (`Activity`) when tracing is enabled for outgoing http requests and `OpenTelemetry.Instrumentation.AspNetCore` writes the `url.query` attribute/tag on spans (`Activity`) when tracing is enabled for incoming http requests. These attributes are defined by the Semantic Conventions for HTTP Spans. Up until version `1.8.1` the values written by `OpenTelemetry.Instrumentation.Http` & `OpenTelemetry.Instrumentation.AspNetCore` will pass-through the raw query string as was sent or received (respectively). This may lead to sensitive information (e.g. EUII - End User Identifiable Information, credentials, etc.) being leaked into telemetry backends (depending on the application(s) being instrumented) which could cause privacy and/or security incidents. Note: Older versions of `OpenTelemetry.Instrumentation.Http` & `OpenTelemetry.Instrumentation.AspNetCore` may use different tag names but have the same vulnerability. The `1.8.1` versions of `OpenTelemetry.Instrumentation.Http` & `OpenTelemetry.Instrumentation.AspNetCore` will now redact by default all values detected on transmitted or received query strings. Users are advised to upgrade. There are no known workarounds for this vulnerability.