Tornado vulnerable to excessive logging caused by malformed multipart form data

CAO 7.5CVE-2025-47287 · GHSA-7cx3-6m66-7c5m · PYSEC-2026-1974 · Công bố 15/05/2025 · cập nhật 17/06/2026

Tóm tắt nhanh

CVE-2025-47287 là lỗ hổng mức CAO (CVSS 7.5) ảnh hưởng tornado, tornado (tornadoweb).
Xác suất bị khai thác trong 30 ngày tới (EPSS): 0.74%, cao hơn 54.8% các lỗ hổng khác.
Cách xử lý: cập nhật lên 6.5, 6.5.0 hoặc mới hơn.

Gói / sản phẩm	Phiên bản bị ảnh hưởng	Phiên bản đã vá
tornado PyPI	`< 6.5`	`6.5`
tornado tornadoweb	`< 6.5.0`	`6.5.0`

Mô tả

Summary

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.

Affected versions

All versions of Tornado prior to 6.5 are affected. The vulnerable parser is enabled by default.

Solution

Upgrade to Tornado version 6.5. In the meantime, risk can be mitigated by blocking Content-Type: multipart/form-data in a proxy.

Mô tả của NVD

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.