---
cve: "CVE-2026-81871"
severity: "MEDIUM"
cvss: 6.3
epss: "3.3%"
vendor: "open-telemetry"
kev: false
exploited: false
published: "2026-09-16 21:17:22"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-17T23:59:47+02:00"
---

# CVE-2026-81871

> 6.3 MEDIUM · 🧪 PoC

## Beschreibung

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.

## CVSS-Vektor

```
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
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Keine | bad |

## Patch verfügbar (OSV)

- ced177b79530b937530c4f9030ab2115367c5de9 (Commit)

## Referenzen

- <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>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-81871) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_