{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-126360", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-11-10T21:12:01.228Z", "datePublished": "2026-11-12T22:24:22.023Z", "dateUpdated": "2026-11-12T22:24:22.023Z"}, "containers": {"cna": {"title": "OpenTelemetry Python: Denial of service through quadratic-time traceparent parsing in opentelemetry-api", "problemTypes": [{"descriptions": [{"cweId": "CWE-1333", "lang": "en", "description": "CWE-1333: Inefficient Regular Expression Complexity", "type": "CWE"}]}], "metrics": [{"cvssV3_1": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}}], "references": [{"name": "https://github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-mf5v-w3w3-f6cg", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/open-telemetry/opentelemetry-python/security/advisories/GHSA-mf5v-w3w3-f6cg"}, {"name": "https://github.com/open-telemetry/opentelemetry-python/pull/5818", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-telemetry/opentelemetry-python/pull/5818"}, {"name": "https://github.com/open-telemetry/opentelemetry-python/pull/5856", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-telemetry/opentelemetry-python/pull/5856"}, {"name": "https://github.com/open-telemetry/opentelemetry-python/commit/78123a2755c907c602e02352aebed4be86aa5350", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-telemetry/opentelemetry-python/commit/78123a2755c907c602e02352aebed4be86aa5350"}, {"name": "https://github.com/open-telemetry/opentelemetry-python/commit/faa72dae511ae64a7bf8ca63eff9ad4387d0b939", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-telemetry/opentelemetry-python/commit/faa72dae511ae64a7bf8ca63eff9ad4387d0b939"}, {"name": "https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.45.2", "tags": ["x_refsource_MISC"], "url": "https://github.com/open-telemetry/opentelemetry-python/releases/tag/v1.45.2"}], "affected": [{"vendor": "open-telemetry", "product": "opentelemetry-python", "versions": [{"version": "< 1.45.2", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-11-12T22:24:22.023Z"}, "descriptions": [{"lang": "en", "value": "OpenTelemetry Python provides the Python API and SDK for OpenTelemetry. Prior to 1.45.2, TraceContextTextMapPropagator.extract() in opentelemetry-api can perform quadratic-time regular-expression backtracking on a malformed traceparent value containing a trace-context prefix, a long whitespace sequence, and an embedded newline. Exploitation requires an attacker-controlled carrier that preserves embedded newlines and permits a sufficiently large value, because conforming HTTP header values cannot contain embedded newlines. JSON-based carriers, including applicable MCP request metadata integrations, can preserve the required newline depending on the SDK, instrumentation, and message-size limits. Parsing on an asynchronous server's event-loop thread can consume excessive CPU and delay unrelated requests, while the advisory does not establish disclosure, modification, or code execution. This issue is fixed in version 1.45.2."}], "source": {"advisory": "GHSA-mf5v-w3w3-f6cg", "discovery": "UNKNOWN"}}}}

{}

{}

{}

{}