CVE-2026-49855: Tornado is a Python web framework and asynchronous networking library. Prior to 6.5.6, Tornado gzip decompression routines processed limited-size chunks but…

PriorityP343high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

0.57%

44.1th percentile

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.

Affected

2 ranges

Vendor	Product	Version range	Fixed in
tornadoweb	tornado	< 6.5.6	6.5.6
tornadoweb	tornado	>= 0 < 6.5.6	6.5.6

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