CVE-2026-49855

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{"affected": [{"affectedData": [{"product": "tornado", "vendor": "tornadoweb", "versions": [{"status": "affected", "version": "< 6.5.6"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "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."}, {"lang": "es", "value": "Tornado es un framework web de Python y una biblioteca de red as\u00edncrona. Antes de la versi\u00f3n 6.5.6, las rutinas de descompresi\u00f3n gzip de Tornado procesaban fragmentos de tama\u00f1o limitado pero no aplicaban un l\u00edmite general a los fragmentos descomprimidos acumulados, lo que permit\u00eda a un servidor malicioso accedido por SimpleAsyncHTTPClient o un HTTPServer configurado con decompress_request=True consumir memoria de forma efectivamente ilimitada. Este problema est\u00e1 solucionado en la versi\u00f3n 6.5.6."}], "id": "CVE-2026-49855", "lastModified": "2026-10-24T21:10:00.130", "metrics": {"cvssMetricV31": [{"cvssData": {"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"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-49855", "options": [{"exploitation": "none"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-07-16T14:55:32.574509Z", "version": "2.0.3"}}]}, "published": "2026-07-14T21:17:02.437", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/commit/ff808b33adc52d89a549376a5e3628e92abbc8ff"}, {"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/pull/3626"}, {"source": "security-advisories@github.com", "url": "https://github.com/tornadoweb/tornado/security/advisories/GHSA-mgf9-4vpg-hj56"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-409"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

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