Bug 2522081

Summary:	CVE-2026-49855 python-flit: Tornado: Denial of Service via uncontrolled gzip decompression memory consumption [fedora-all]
Product:	[Fedora] Fedora	Reporter:	Ganesh <gnaik>
Component:	python-flit	Assignee:	Maxwell G <maxwell>
Status:	NEW ---	QA Contact:	Fedora Extras Quality Assurance <extras-qa>
Severity:	high	Docs Contact:
Priority:	high
Version:	rawhide	CC:	epel-packagers-sig, maxwell, michel, python-packagers-sig
Target Milestone:	---	Keywords:	Security, SecurityTracking
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:	{"flaws": ["9697158f-853c-4d52-8836-1cf2e536c70b"]}
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	2500686

Description Ganesh 2026-08-24 17:07:25 UTC

Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

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.