{"schemaVersion":3,"id":"CVE-2026-49855","aliases":["GHSA-mgf9-4vpg-hj56","PYSEC-2026-3389","UBUNTU-CVE-2026-49855","DEBIAN-CVE-2026-49855","CGA-9p7x-vm7g-7xvh","CGA-mcww-223h-qrv9","CGA-gppg-r36g-g6xv","CGA-r9j7-96f3-2874"],"status":"published","duplicateOf":null,"title":null,"description":"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. 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