CVE-2026-31958
Tornado has a DoS due to too many multipart parts
Description
Tornado is a Python web framework and asynchronous networking library. In versions of Tornado prior to 6.5.5, the only limit on the number of parts in multipart/form-data is the max_body_size setting (default 100MB). Since parsing occurs synchronously on the main thread, this creates the possibility of denial-of-service due to the cost of parsing very large multipart bodies with many parts. This vulnerability is fixed in 6.5.5.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:NAttack VectorNetwork
AC:LAttack ComplexityLow
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
Red Hat Inc.
commercial·USaka red hat
Canonical Ltd.
commercial·GBaka canonical
Сообщество свободного программного обеспечения
oss-projectaka fsf
ООО «Ред Софт»
commercial·RUaka red soft
АО «ИВК»
commercial·RUaka ivk
FriendFeed
oss-projectaka tornado
and 2 more affected products View all →
Exploitability
Official Patch Available
Attack Graph
Products CVE Techniques Tactics
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MITRE ATT&CK
1 technique Impact
References
https://github.com/tornadoweb/tornado/releases/tag/v6.5.5
github.com
https://lists.debian.org/debian-lts-announce/2026/04/msg00000.html
lists.debian.org
https://github.com/tornadoweb/tornado/security/advisories/GHSA-qjxf-f2mg-c6mc
github.com
and 14 more references View all →
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