CVE-2026-81871 (GCVE-0-2026-81871)
Vulnerability from cvelistv5 – Published: 2026-09-16 20:43 – Updated: 2026-09-17 19:24
VLAI
EPSS
VEX
Title
OpenTelemetry-Go: Log gRPC exporter ignores env TLS certs, bypassing mTLS/pinning
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-17 17:10 UTC
CWE
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/open-telemetry/opentelemetry-g… | x_refsource_CONFIRM |
| https://github.com/open-telemetry/opentelemetry-g… | x_refsource_MISC |
| https://github.com/open-telemetry/opentelemetry-g… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| open-telemetry | opentelemetry-go |
Affected:
< 0.21.0
|
guessed |
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}
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"lastModified": "2026-09-30T17:31:44.573",
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"modifiedAttackComplexity": "NOT_DEFINED",
"modifiedAttackRequirements": "NOT_DEFINED",
"modifiedAttackVector": "NOT_DEFINED",
"modifiedPrivilegesRequired": "NOT_DEFINED",
"modifiedSubAvailabilityImpact": "NOT_DEFINED",
"modifiedSubConfidentialityImpact": "NOT_DEFINED",
"modifiedSubIntegrityImpact": "NOT_DEFINED",
"modifiedUserInteraction": "NOT_DEFINED",
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"modifiedVulnConfidentialityImpact": "NOT_DEFINED",
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Sightings
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|---|
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
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They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.