{"id":"UBUNTU-CVE-2026-81871","details":"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.","modified":"2026-09-18T12:30:35.939829819Z","published":"2026-09-18T00:00:00Z","upstream":["CVE-2026-81871"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-81871"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-81871"},{"type":"REPORT","url":"https://github.com/open-telemetry/opentelemetry-go/commit/c65d435b43e5e6b82310e6b18dd4cdcb8ac63a0c"},{"type":"REPORT","url":"https://github.com/open-telemetry/opentelemetry-go/releases/tag/exporters/otlp/otlplog/otlploggrpc/v0.21.0"},{"type":"REPORT","url":"https://github.com/open-telemetry/opentelemetry-go/security/advisories/GHSA-w34q-cm8f-9c5x"}],"affected":[{"package":{"name":"golang-opentelemetry-otel","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/golang-opentelemetry-otel?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.1.0-2"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-opentelemetry-otel-dev","binary_version":"1.1.0-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-81871.json"}},{"package":{"name":"golang-opentelemetry-otel","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/golang-opentelemetry-otel?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.16.0-1"],"ecosystem_specific":{"binaries":[{"binary_version":"1.16.0-1","binary_name":"golang-opentelemetry-otel-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-81871.json"}},{"package":{"name":"golang-opentelemetry-otel","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/golang-opentelemetry-otel?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.31.0-4","1.31.0-5","1.31.0-6"],"ecosystem_specific":{"binaries":[{"binary_version":"1.31.0-6","binary_name":"golang-opentelemetry-otel-dev"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-81871.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"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"},{"type":"Ubuntu","score":"medium"}]}