Denial of service via unbounded error-response reads
Published Apr 23, 2026 · Updated Apr 23, 2026
Denial of service in OpenTelemetry .NET 1.13.1 through 1.15.1 allows attackers to exhaust application memory via OTLP error responses. The OTLP exporter fully reads non-200 gRPC or HTTP/protobuf response bodies into memory without an upper bound. Exploitation requires an attacker-controlled collector endpoint or a man-in-the-middle position and an extremely large response, resulting in memory exhaustion and service interruption.
Summary
What happened
Denial of service in OpenTelemetry .NET 1.13.1 through 1.15.1 allows attackers to exhaust application memory via OTLP error responses. The OTLP exporter fully reads non-200 gRPC or HTTP/protobuf response bodies into memory without an upper bound. Exploitation requires an attacker-controlled collector endpoint or a man-in-the-middle position and an extremely large response, resulting in memory exhaustion and service interruption.
The record
- CVE
- CVE-2026-40182
- Published
- Apr 23, 2026
- Updated
- Apr 23, 2026
- Vendor
- OpenTelemetry
- Product
- OpenTelemetry .NET
- Classifications
- CWE-789, T1499.004
- Attack vector
- adjacent
- Privileges
- unauthenticated
Timeline
How it unfolded
- Apr 23, 2026CVE publishedPublication date reported by the CVE source.
- Apr 23, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=>= 1.13.1, < 1.15.2
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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