CVEvulnerability
CVE-2025-47287
7.5 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2025-05-15
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-770
Description
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.
Affected configurations
• tornadoweb tornado (< 6.5.0)
• debian debian linux 11.0
Related
Weakness · CWE (1)
- CWE-770 Allocation of Resources Without Limits or Throttling weakness
References
- 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