{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-49855","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","state":"PUBLISHED","assignerShortName":"GitHub_M","dateReserved":"2026-06-01T22:03:19.640Z","datePublished":"2026-07-14T20:45:02.982Z","dateUpdated":"2026-07-16T14:56:38.904Z"},"containers":{"cna":{"title":"tornado AsyncHTTPClient accumulates decompressed chunks without size limit (gzip bomb)","problemTypes":[{"descriptions":[{"cweId":"CWE-409","lang":"en","description":"CWE-409: Improper Handling of Highly Compressed Data (Data Amplification)","type":"CWE"}]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","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:H","version":"3.1"}}],"references":[{"name":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-mgf9-4vpg-hj56","tags":["x_refsource_CONFIRM"],"url":"https://github.com/tornadoweb/tornado/security/advisories/GHSA-mgf9-4vpg-hj56"},{"name":"https://github.com/tornadoweb/tornado/pull/3626","tags":["x_refsource_MISC"],"url":"https://github.com/tornadoweb/tornado/pull/3626"},{"name":"https://github.com/tornadoweb/tornado/commit/ff808b33adc52d89a549376a5e3628e92abbc8ff","tags":["x_refsource_MISC"],"url":"https://github.com/tornadoweb/tornado/commit/ff808b33adc52d89a549376a5e3628e92abbc8ff"}],"affected":[{"vendor":"tornadoweb","product":"tornado","versions":[{"version":"< 6.5.6","status":"affected"}]}],"providerMetadata":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-07-14T20:45:02.982Z"},"descriptions":[{"lang":"en","value":"Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chunks but did not enforce an overall limit on accumulated decompressed chunks, allowing a malicious server accessed by SimpleAsyncHTTPClient or an HTTPServer configured with decompress_request=True to consume effectively unlimited memory. This issue is fixed in version 6.5.6."}],"source":{"advisory":"GHSA-mgf9-4vpg-hj56","discovery":"UNKNOWN"}},"adp":[{"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-07-16T14:55:32.574509Z","id":"CVE-2026-49855","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-07-16T14:56:38.904Z"}}]}}