Answer in brief
CVE-2026-81871 records a Medium severity (CVSS 0.0) vulnerability in OpenTelemetry-Go: Log gRPC exporter ignores env TLS certs, bypassing mTLS/pinning. The current sources do not mark it as known exploited. The current feed maps open-telemetry/opentelemetry-go (generic), go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc (go), go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc (go). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 0.0. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps open-telemetry/opentelemetry-go (generic), go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc (go), go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc (go). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| open-telemetry/opentelemetry-gogeneric | <0.21.0 | 0.21.0 |
| go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpcgo | <0.21.0 | 0.21.0 |
| go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpcgo | >=0 <0.21.0 | 0.21.0 |
Published upstream
Sep 16, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 16, 2026
OpenTelemetry-Go is the Go implementation of OpenTelemetry. Prior to version 0.21.0, the exporters/otlp/otlplog/otlploggrpc package loads OTEL_EXPORTER_OTLP_LOGS_CERTIFICATE, OTEL_EXPORTER_OTLP_CERTIFICATE, and related client certificate environment variables through loadEnvTLS into cfg.tlsCfg, but newGRPCDialOptions does not apply cfg.tlsCfg when creating gRPC transport credentials. The environment-only TLS path instead uses credentials.NewTLS with system roots and no configured client certificate, bypassing intended private CA pinning and mutual TLS unless the application also supplies WithTLSCredentials. A network attacker able to intercept or spoof the collector connection with a system-trusted certificate can read or alter log telemetry. This issue is fixed in version 0.21.0.
Quoted source text, attributed separately from HOL analysis.