CVE-2026-40891
5.3 · MEDIUMOverview
CVE-2026-40891 is a medium-severity vulnerability affecting opentelemetry opentelemetry. It was published on April 23, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
Technical Description
OpenTelemetry dotnet is a dotnet telemetry framework. From 1.13.1 to before 1.15.2, When exporting telemetry over gRPC using the OpenTelemetry Protocol (OTLP), the exporter may parse a server-provided grpc-status-details-bin trailer during retry handling. Prior to the fix, a malformed trailer could encode an extremely large length-delimited protobuf field which was used directly for allocation, allowing excessive memory allocation and potential denial of service (DoS). This vulnerability is fixed in 1.15.2.
Remediation
Check the references section for vendor advisories and patches from opentelemetry. Update opentelemetry to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| opentelemetry | opentelemetry | >= 1.13.1, < 1.15.3 | Affected |
Frequently Asked Questions
What is CVE-2026-40891?
CVE-2026-40891 is a medium-severity vulnerability affecting opentelemetry opentelemetry. It was published on April 23, 2026 and has a CVSS 3.1 base score of 5.3 (MEDIUM).
How severe is CVE-2026-40891?
This vulnerability has a CVSS 3.1 base score of 5.3, rated MEDIUM. It requires local or adjacent network access to exploit. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-40891?
Check the references section for vendor advisories and patches from opentelemetry. Update opentelemetry to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40891?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40891 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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