OpenTelemetry-cpp is the C++ implementation of OpenTelemetry. Prior to release 1.27.0, the OTLP HTTP exporters (traces/metrics/logs) read the full HTTP response into an in-memory vector of bytes without a size cap. This is exploitable for memory exhaustion when the configured collector endpoint is attacker-controlled (or a network attacker can MITM the exporter connection). This vulnerability is fixed in opentelemetry-cpp release 1.27.0.

OpenTelemetry-Go is the Go implementation of OpenTelemetry. Versions 1.41.0 and 1.43.0 removed raw-length rejection and it causes `Parse` to process arbitrarily large/invalid baggage headers and log errors, enabling DoS via oversized inputs. Versions 1.42.0 and 1.44.0 fix the issue.

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. 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-Go is the Go implementation of OpenTelemetry. From 1.15.0 to 1.42.0, the fix for CVE-2026-24051 changed the Darwin ioreg command to use an absolute path but left the BSD kenv command using a bare name, allowing the same PATH hijacking attack on BSD and Solaris platforms. This vulnerability is fixed in 1.43.0.

OpenTelemetry-Go is the Go implementation of OpenTelemetry. Prior to 1.43.0, the otlp HTTP exporters (traces/metrics/logs) read the full HTTP response body into an in-memory bytes.Buffer without a size cap. This is exploitable for memory exhaustion when the configured collector endpoint is attacker-controlled (or a network attacker can mitm the exporter connection). This vulnerability is fixed in 1.43.0.

OpenTelemetry-Go is the Go implementation of OpenTelemetry. From 1.36.0 to 1.40.0, multi-value baggage: header extraction parses each header field-value independently and aggregates members across values. This allows an attacker to amplify cpu and allocations by sending many baggage: header lines, even when each individual value is within the 8192-byte per-value parse limit. This vulnerability is fixed in 1.41.0.

OpenTelemetry-Go is the Go implementation of OpenTelemetry. The OpenTelemetry Go SDK in version v1.20.0-1.39.0 is vulnerable to Path Hijacking (Untrusted Search Paths) on macOS/Darwin systems. The resource detection code in sdk/resource/host_id.go executes the ioreg system command using a search path. An attacker with the ability to locally modify the PATH environment variable can achieve Arbitrary Code Execution (ACE) within the context of the application. A fix was released with v1.40.0.

A missing permission check in Jenkins OpenTelemetry Plugin 3.1543.v8446b_92b_cd64 and earlier allows attackers with Overall/Read permission to connect to an attacker-specified URL using attacker-specified credentials IDs obtained through another method, capturing credentials stored in Jenkins.

The OpenTelemetry Collector offers a vendor-agnostic implementation on how to receive, process and export telemetry data. An unsafe decompression vulnerability allows unauthenticated attackers to crash the collector via excessive memory consumption. OTel Collector version 0.102.1 fixes this issue. It is also fixed in the confighttp module version 0.102.0 and configgrpc module version 0.102.1.

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.

OpenTelemetry-Go Contrib is a collection of third-party packages for OpenTelemetry-Go. Starting in version 0.37.0 and prior to version 0.46.0, the grpc Unary Server Interceptor out of the box adds labels `net.peer.sock.addr` and `net.peer.sock.port` that have unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent. An attacker can easily flood the peer address and port for requests. Version 0.46.0 contains a fix for this issue. As a workaround to stop being affected, a view removing the attributes can be used. The other possibility is to disable grpc metrics instrumentation by passing `otelgrpc.WithMeterProvider` option with `noop.NewMeterProvider`.

OpenTelemetry-Go Contrib is a collection of third-party packages for OpenTelemetry-Go. A handler wrapper out of the box adds labels `http.user_agent` and `http.method` that have unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent to it. HTTP header User-Agent or HTTP method for requests can be easily set by an attacker to be random and long. The library internally uses `httpconv.ServerRequest` that records every value for HTTP `method` and `User-Agent`. In order to be affected, a program has to use the `otelhttp.NewHandler` wrapper and not filter any unknown HTTP methods or User agents on the level of CDN, LB, previous middleware, etc. Version 0.44.0 fixed this issue when the values collected for attribute `http.request.method` were changed to be restricted to a set of well-known values and other high cardinality attributes were removed. As a workaround to stop being affected, `otelhttp.WithFilter()` can be used, but it requires manual careful configuration to not log certain requests entirely. For convenience and safe usage of this library, it should by default mark with the label `unknown` non-standard HTTP methods and User agents to show that such requests were made but do not increase cardinality. In case someone wants to stay with the current behavior, library API should allow to enable it.

OpenTelemetry, also known as OTel for short, is a vendor-neutral open-source Observability framework for instrumenting, generating, collecting, and exporting telemetry data such as traces, metrics, logs. Autoinstrumentation out of the box adds the label `http_method` that has unbound cardinality. It leads to the server's potential memory exhaustion when many malicious requests are sent. HTTP method for requests can be easily set by an attacker to be random and long. In order to be affected program has to be instrumented for HTTP handlers and does not filter any unknown HTTP methods on the level of CDN, LB, previous middleware, etc. This issue has been patched in version 0.41b0.