DoS vulnerability for high cardinality metrics in opentelemetry-go-contrib

Summary

opentelemetry-go-contrib is a collection of extensions for OpenTelemetry-Go. The v0.38.0 release of `go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp` uses the `httpconv.ServerRequest` function to annotate metric measurements for the `http.server.request_content_length`, `http.server.response_content_length`, and `http.server.duration` instruments. The `ServerRequest` function sets the `http.target` attribute value to be the whole request URI (including the query string)[^1]. The metric instruments do not "forget" previous measurement attributes when `cumulative` temporality is used, this means the cardinality of the measurements allocated is directly correlated with the unique URIs handled. If the query string is constantly random, this will result in a constant increase in memory allocation that can be used in a denial-of-service attack. This issue has been addressed in version 0.39.0. Users are advised to upgrade. There are no known workarounds for this issue.

Timeline

1. Feb 8, 2023, 7:21 PM UTCCVE published
2. Mar 10, 2025, 9:02 PM UTCCISA SSVC assessment

   Exploitation: poc · Automatable: yes · Technical impact: partial

3. Mar 10, 2025, 9:14 PM UTCRecord last updated

Affected versions

• open-telemetry opentelemetry-go-contrib

  From 0.38.0 · fixed in 0.39.0

• go.opentelemetry.io/contrib/instrumentation/net/http/otelhttpGo

  From 0.38.0 · fixed in 0.39.0

• go.opentelemetry.io/contrib/instrumentation/github.com/astaxie/beego/otelbeegoGo

  From 0.38.0 · fixed in 0.39.0

References 2