{"id":"CVE-2026-40891","revision":null,"records":[{"revision":"330f28d4c8b44f11920fcdd1b464fce9","observedAt":"2026-10-23T15:48:27.903+00:00","statement":{"source":"cve-program","id":"CVE-2026-40891","aliases":[],"title":"OpenTelemetry dotnet: Unbounded `grpc-status-details-bin` parsing in OTLP/gRPC retry handling","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.","state":0,"publishedAt":"2026-04-23T17:54:36.033+00:00","modifiedAt":"2026-04-23T18:23:08.858+00:00","affected":[{"ecosystem":"Vendor product","name":"opentelemetry-dotnet","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"open-telemetry\",\n                    \"product\": \"opentelemetry-dotnet\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 1.13.1, < 1.15.3\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"},{"ecosystem":"Vendor product","name":"OpenTelemetry.Exporter.OpenTelemetryProtocol","ranges":[],"versions":[],"rawVersionEvidence":"{\n                    \"vendor\": \"open-telemetry\",\n                    \"product\": \"OpenTelemetry.Exporter.OpenTelemetryProtocol\",\n                    \"versions\": [\n                        {\n                            \"version\": \">= 1.13.1, < 1.15.3\",\n                            \"status\": \"affected\"\n                        }\n                    ]\n                }"}],"metrics":[{"system":"CVSS 3.1","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-mr8r-92fq-pj8p","https://github.com/open-telemetry/opentelemetry-dotnet/pull/5980","https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064"],"sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-40891","license":"CVE Program Terms of Use","key":"cve-program:CVE-2026-40891","identifiers":["CVE-2026-40891"]},"retained":false,"historicalAffected":[]},{"revision":"de695f217dcb4fa0998501afd7c4bc17","observedAt":"2026-10-28T05:02:52.465+00:00","statement":{"source":"euvd","id":"EUVD-2026-25268","aliases":["CVE-2026-40891"],"title":"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 …","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.","state":0,"publishedAt":null,"modifiedAt":null,"affected":[],"metrics":[{"system":"EUVD CVSS 3.1","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.3,"severity":null}],"references":["https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-mr8r-92fq-pj8p","https://github.com/open-telemetry/opentelemetry-dotnet/pull/5980","https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064"],"sourceUrl":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2026-25268","license":"ENISA EUVD · source terms and attribution apply","enrichment":{"sourceStatus":null,"weaknesses":[],"productCriteria":[],"sourceDates":{"datePublished":"Apr 23, 2026, 5:54:36 PM","dateUpdated":"Apr 23, 2026, 6:23:08 PM"},"relatedAdvisories":[],"note":"EUVD source date text has no stated timezone and is retained without inventing a UTC instant. Related bulletin membership is not an alias, common cause or applicability claim. A missing vector with a zero score is treated as unrated. Complete vendor/product and underlying source evidence remains in the original JSON."},"key":"euvd:EUVD-2026-25268","identifiers":["EUVD-2026-25268","CVE-2026-40891"]},"retained":false,"historicalAffected":[]},{"revision":"088c67266f474c4aa4adf3eb76671d50","observedAt":"2026-10-27T10:10:07.342+00:00","statement":{"source":"nvd","id":"CVE-2026-40891","aliases":[],"title":"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 …","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.","state":0,"publishedAt":"2026-04-23T18:16:28.483+00:00","modifiedAt":"2026-10-26T21:10:00.17+00:00","affected":[],"metrics":[{"system":"CVSS 3.1 · security-advisories@github.com · Secondary","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.3,"severity":"MEDIUM"},{"system":"CVSS 3.1 · nvd@nist.gov · Primary","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":5.3,"severity":"MEDIUM"}],"references":["https://github.com/open-telemetry/opentelemetry-dotnet/pull/5980","https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064","https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-mr8r-92fq-pj8p"],"sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-40891","license":"NIST NVD usage terms; underlying source attribution retained","enrichment":{"sourceStatus":"Analyzed","weaknesses":["CWE-789"],"productCriteria":["cpe:2.3:a:opentelemetry:opentelemetry:*:*:*:*:*:.net:*:*"],"sourceDates":{"published":"2026-04-23T18:16:28.483","lastModified":"2026-10-26T21:10:00.170"},"relatedAdvisories":[],"note":"NVD analysis and CPE criteria are source context, not proof that a package or your environment is affected. Complete affected data, logical configurations and SSVC are retained in the original JSON."},"key":"nvd:CVE-2026-40891","identifiers":["CVE-2026-40891"]},"retained":false,"historicalAffected":[]},{"revision":"87310116c4ff4e118a708111f528864c","observedAt":"2026-10-23T16:01:25.029+00:00","statement":{"source":"osv","id":"GHSA-mr8r-92fq-pj8p","aliases":["CVE-2026-40891"],"title":"OpenTelemetry dotnet: Unbounded `grpc-status-details-bin` parsing in OTLP/gRPC retry handling","description":"### Summary\n\nWhen 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).\n\n### Details\n\n#5980 introduced a retry path that parses `grpc-status-details-bin` to extract gRPC retry delay information for retryable responses.\n\nOn that path:\n\n- `OtlpGrpcExportClient` captures `grpc-status-details-bin` from retryable status responses (`ResourceExhausted` / `Unavailable`).\n- `OtlpRetry` invokes `GrpcStatusDeserializer.TryGetGrpcRetryDelay` using this untrusted trailer value.\n- `GrpcStatusDeserializer.DecodeBytes` decoded a protobuf varint length and allocated `new byte[length]` without validating the bounds against the remaining payload size.\n\nA malicious or compromised collector (or a MitM in weakly-protected deployments) could return a crafted `grpc-status-details-bin` payload that forces oversized allocation and memory exhaustion in the instrumented process.\n\n### Impact\n\nIf an OTLP/gRPC endpoint is attacker-controlled (or traffic is intercepted), a crafted retryable response can trigger large allocations during trailer parsing, which may exhaust memory and cause process instability/crash (availability impact / DoS).\n\n### Mitigation\n\nThe application's configured back-end/collector endpoint needs to behave maliciously. If the collector/back-end is a well-behaved implementation response bodies should not be excessively large if a request error occurs.\n\n### Workarounds\n\nNone known.\n\n### Remediation\n\n[#7064](https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064) updates `GrpcStatusDeserializer` to validate decoded length-delimited field sizes before allocation by ensuring the requested length is sane and does not exceed the remaining payload.\n\nThis causes malformed or truncated `grpc-status-details-bin` payloads to fail safely instead of attempting unbounded allocation.","state":0,"publishedAt":"2026-04-23T21:40:29+00:00","modifiedAt":"2026-09-10T03:50:44.892821+00:00","affected":[{"ecosystem":"NuGet","name":"OpenTelemetry.Exporter.OpenTelemetryProtocol","ranges":[{"type":"ECOSYSTEM","events":[{"kind":"introduced","version":"1.13.1"},{"kind":"fixed","version":"1.15.3"}]}],"versions":["1.13.1","1.14.0","1.15.0","1.15.1","1.15.2"],"rawVersionEvidence":null}],"metrics":[{"system":"CVSS_V3","vector":"CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H","score":null,"severity":null},{"system":"Publisher rating","vector":null,"score":null,"severity":"MODERATE"}],"references":["https://github.com/open-telemetry/opentelemetry-dotnet/security/advisories/GHSA-mr8r-92fq-pj8p","https://nvd.nist.gov/vuln/detail/CVE-2026-40891","https://github.com/open-telemetry/opentelemetry-dotnet/pull/5980","https://github.com/open-telemetry/opentelemetry-dotnet/pull/7064","https://github.com/open-telemetry/opentelemetry-dotnet"],"sourceUrl":"https://github.com/advisories/GHSA-mr8r-92fq-pj8p","license":"GitHub Advisory Database · CC-BY-4.0","key":"osv:GHSA-mr8r-92fq-pj8p","identifiers":["GHSA-mr8r-92fq-pj8p","CVE-2026-40891"]},"retained":false,"historicalAffected":[]}],"coverage":[{"source":"cisa-kev:global","scope":"Complete CISA KEV catalog; all vendors. Missing entries do not establish absence of exploitation.","generation":"2026-10-30T00:54:54.8582963+00:00","complete":true,"records":1764,"lastAttemptAt":"2026-10-30T00:54:54.8582963+00:00","lastSuccessAt":"2026-10-30T00:54:55.0088391+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:55.0088398+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"cve-program","scope":"Official CVE Program baseline and cumulative hourly delta; all vendors, published and rejected records","generation":"cve-7e2c4e7288f2c464ad8c61f3bb6017374714faedcc781283ac06a706ee1a820b-8739c76e681f900923b900c9df0ef75cf421d39cabb54650c4b9ad19b6a76d85","complete":true,"records":416807,"lastAttemptAt":"2026-10-30T00:54:38.6898381+00:00","lastSuccessAt":"2026-10-30T00:54:38.6858592+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:38.6898381+00:00","snapshotPublishedAt":"2026-10-30T00:40:10+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"euvd","scope":"Rolling EUVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global EUVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-5ad2d2d1ff1947fe944c0f4aa4d1bc11","complete":false,"records":13504,"lastAttemptAt":"2026-10-30T01:07:07.5184772+00:00","lastSuccessAt":"2026-10-30T01:07:07.514+00:00","error":"18 identifier lookups failed; latest failures include HTTP 403. Other identifiers were checked independently.","lastVerifiedAt":"2026-10-30T01:07:07.514+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13079,"expectedIdentifiers":13587,"failedIdentifiers":18},{"source":"first-epss:nuget","scope":"FIRST EPSS for explicit CVE aliases in the collected public NuGet archive. Not a global EPSS backfill.","generation":"2026-10-30T00:54:54.8582963+00:00","complete":true,"records":1094,"lastAttemptAt":"2026-10-30T00:54:54.8582963+00:00","lastSuccessAt":"2026-10-30T00:54:55.0097322+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:55.0097324+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"nvd","scope":"Rolling NVD lookups of CVE aliases in current public OSV archives; 500 identifiers per refresh, rechecked after 48 hours. Not a global NVD catalog. Successful not-found lookups count as checked; they do not imply withdrawal or safety. No reader inventory is sent.","generation":"enrichment-c39f89b50d5243318487ad216daf7ffb","complete":true,"records":13527,"lastAttemptAt":"2026-10-30T00:54:55.5485585+00:00","lastSuccessAt":"2026-10-29T22:50:37.74+00:00","error":null,"lastVerifiedAt":"2026-10-29T22:50:37.74+00:00","snapshotPublishedAt":null,"importing":false,"stagedRecords":0,"checkedIdentifiers":13587,"expectedIdentifiers":13587,"failedIdentifiers":0},{"source":"osv:Go","scope":"Complete OSV Go ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"go-9016081e9e88f5929902343d85df87c5c4a1486b10ab07bc6c4f53f98f358871","complete":true,"records":9806,"lastAttemptAt":"2026-10-30T00:54:39.0679477+00:00","lastSuccessAt":"2026-10-29T17:17:25.9359141+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:39.0679477+00:00","snapshotPublishedAt":"2026-10-29T16:48:29+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:NuGet","scope":"Complete OSV NuGet ecosystem archive, including GitHub Advisory Database records; NuGet version matching only","generation":"nuget-2de9ccc5290f060c7aa63f89c25dd76f655a64ba1aba7c05c97fa3bee4f09899","complete":true,"records":1967,"lastAttemptAt":"2026-10-30T00:54:38.8530111+00:00","lastSuccessAt":"2026-10-28T20:55:34.2982937+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:38.8530111+00:00","snapshotPublishedAt":"2026-10-28T20:03:08+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:crates.io","scope":"Complete OSV crates.io ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"crates.io-5221f6b645588be0464ab0e16e8adfe42d1ccd8f841048d2bd4d0c1cf79fd6b1","complete":true,"records":3014,"lastAttemptAt":"2026-10-30T00:54:54.8235985+00:00","lastSuccessAt":"2026-10-30T00:54:54.6624163+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:54.8235985+00:00","snapshotPublishedAt":"2026-10-30T00:48:06+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null},{"source":"osv:npm","scope":"Complete OSV npm ecosystem archive, including withdrawn and malicious-package source records; statement counts are not unique CVE counts","generation":"npm-ec5b13e78c39945726a720832da7660d2774969f16e2a34f99460c135811abd5","complete":true,"records":230948,"lastAttemptAt":"2026-10-30T00:54:38.9583185+00:00","lastSuccessAt":"2026-10-29T22:50:35.0693267+00:00","error":null,"lastVerifiedAt":"2026-10-30T00:54:38.9583185+00:00","snapshotPublishedAt":"2026-10-29T22:33:13+00:00","importing":false,"stagedRecords":0,"checkedIdentifiers":null,"expectedIdentifiers":null,"failedIdentifiers":null}]}