{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-115927", "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "state": "PUBLISHED", "assignerShortName": "GitHub_M", "dateReserved": "2026-10-23T20:21:45.108Z", "datePublished": "2026-10-26T19:37:40.584Z", "dateUpdated": "2026-10-26T19:37:40.584Z"}, "containers": {"cna": {"title": "Tornado: Event loop blocking and excess memory use from chunked bodies with many small chunks", "problemTypes": [{"descriptions": [{"cweId": "CWE-400", "lang": "en", "description": "CWE-400: Uncontrolled Resource Consumption", "type": "CWE"}]}, {"descriptions": [{"cweId": "CWE-770", "lang": "en", "description": "CWE-770: Allocation of Resources Without Limits or Throttling", "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/tornadoweb/tornado/security/advisories/GHSA-r4j5-9xpp-3985", "tags": ["x_refsource_CONFIRM"], "url": "https://github.com/tornadoweb/tornado/security/advisories/GHSA-r4j5-9xpp-3985"}, {"name": "https://github.com/tornadoweb/tornado/pull/3773", "tags": ["x_refsource_MISC"], "url": "https://github.com/tornadoweb/tornado/pull/3773"}, {"name": "https://github.com/tornadoweb/tornado/commit/ceab33581489751a66fba8566ad6d5960d4b01c8", "tags": ["x_refsource_MISC"], "url": "https://github.com/tornadoweb/tornado/commit/ceab33581489751a66fba8566ad6d5960d4b01c8"}, {"name": "https://github.com/tornadoweb/tornado/releases/tag/v6.6.0", "tags": ["x_refsource_MISC"], "url": "https://github.com/tornadoweb/tornado/releases/tag/v6.6.0"}], "affected": [{"vendor": "tornadoweb", "product": "tornado", "versions": [{"version": "< 6.6.0", "status": "affected"}]}], "providerMetadata": {"orgId": "a0819718-46f1-4df5-94e2-005712e83aaa", "shortName": "GitHub_M", "dateUpdated": "2026-10-26T19:37:40.584Z"}, "descriptions": [{"lang": "en", "value": "Tornado is a Python web framework and asynchronous networking library. Prior to 6.6.0, Tornado decodes HTTP/1.1 chunked transfer encoding by processing body data that has already arrived without yielding to the event loop. A remote unauthenticated peer can send millions of one-byte chunks to monopolize the process event loop and stall every other connection served by that process, while lowering max_body_size only limits the duration of each request. For handlers that do not use @stream_request_body, retaining each chunk as a separate object can consume roughly twenty times the received body size, and SimpleAsyncHTTPClient has the same event-loop behavior when reading a response from a malicious server. This issue is fixed in version 6.6.0."}], "source": {"advisory": "GHSA-r4j5-9xpp-3985", "discovery": "UNKNOWN"}}}}

{}

{"affected": [{"affectedData": [{"product": "tornado", "vendor": "tornadoweb", "versions": [{"status": "affected", "version": "< 6.6.0"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Tornado is a Python web framework and asynchronous networking library. Prior to 6.6.0, Tornado decodes HTTP/1.1 chunked transfer encoding by processing body data that has already arrived without yielding to the event loop. A remote unauthenticated peer can send millions of one-byte chunks to monopolize the process event loop and stall every other connection served by that process, while lowering max_body_size only limits the duration of each request. For handlers that do not use @stream_request_body, retaining each chunk as a separate object can consume roughly twenty times the received body size, and SimpleAsyncHTTPClient has the same event-loop behavior when reading a response from a malicious server. This issue is fixed in version 6.6.0."}], "id": "CVE-2026-115927", "lastModified": "2026-10-26T20:17:52.523", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "security-advisories@github.com", "type": "Secondary"}]}, "published": "2026-10-26T20:17:52.397", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/commit/ceab33581489751a66fba8566ad6d5960d4b01c8"}, {"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/pull/3773"}, {"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/releases/tag/v6.6.0"}, {"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/security/advisories/GHSA-r4j5-9xpp-3985"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-400"}, {"lang": "en", "value": "CWE-770"}], "source": "security-advisories@github.com", "type": "Primary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,6.6.0)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "tornado", "source": "cna", "vendor": "tornadoweb"}, "product": "tornado", "vendor": "tornadoweb"}], "created": "2026-10-26T20:45:13.961850+00:00", "updated": "2026-10-26T21:00:10.151203+00:00", "vendors": ["tornadoweb", "tornadoweb$PRODUCT$tornado"]}