{"id":"CVE-2026-81871","revision":"9fe8be0d21504b7d9b5a01dc556d3fe3","records":[{"revision":"9fe8be0d21504b7d9b5a01dc556d3fe3","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-81871","aliases":[],"title":"OpenTelemetry-Go: Log gRPC exporter ignores env TLS certs, bypassing mTLS/pinning","description":"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.","state":0,"publishedAt":"2026-09-16T20:43:40.119+00:00","modifiedAt":"2026-09-17T19:24:00.081+00:00","affected":[{"ecosystem":"Vendor product","name":"opentelemetry-go","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"open-telemetry\",\n                    \"product\": \"opentelemetry-go\",\n                    \"versions\": [\n                        {\n                            \"version\": \"< 0.21.0\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","score":6.3,"severity":"MEDIUM"}],"references":["https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-w34q-cm8f-9c5x","https://github.com/open-telemetry/opentelemetry-go/commit/c65d435b43e5e6b82310e6b18dd4cdcb8ac63a0c","https://github.com/open-telemetry/opentelemetry-go/releases/tag/exporters/otlp/otlplog/otlploggrpc/v0.21.0"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-81871","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-81871","identifiers":["CVE-2026-81871"]},"retained":false,"historicalAffected":[]}],"coverage":[]}