CVE-2025-47287

Tornado is a Python web framework and asynchronous networking library. When Tornado's ``multipart/form-data`` parser encounters certain errors, it logs a warning but continues trying to parse the remainder of the data. This allows remote attackers to generate an extremely high volume of logs, constituting a DoS attack. This DoS is compounded by the fact that the logging subsystem is synchronous. All versions of Tornado prior to 6.5.0 are affected. The vulnerable parser is enabled by default. Upgrade to Tornado version 6.50 to receive a patch. As a workaround, risk can be mitigated by blocking `Content-Type: multipart/form-data` in a proxy.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/tornadoweb/tornado/commit/b39b892bf78fe8fea01dd45199aa88307e7162f3	Patch
https://github.com/tornadoweb/tornado/security/advisories/GHSA-7cx3-6m66-7c5m	Vendor Advisory
https://lists.debian.org/debian-lts-announce/2025/05/msg00038.html	Mailing List Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:tornadoweb:tornado:*:*:*:*:*:*:*:*

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-05-15 22:15

Updated : 2025-12-23 19:19

NVD link : CVE-2025-47287

Mitre link : CVE-2025-47287

CVE.ORG link : CVE-2025-47287

JSON object : View

Products Affected

debian

debian_linux

tornadoweb

tornado

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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