CVE-2025-47287
Tornado vulnerable to excessive logging caused by malformed multipart form data
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Tornado vulnerable to excessive logging caused by malformed multipart form data
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.
Reserved 2025-05-05 | Published 2025-05-15 | Updated 2025-05-29 | Assigner GitHub_MCWE-770: Allocation of Resources Without Limits or Throttling
github.com/...ornado/security/advisories/GHSA-7cx3-6m66-7c5m
github.com/...ommit/b39b892bf78fe8fea01dd45199aa88307e7162f3
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