Update dependency tornado to v6.5.5 [SECURITY]

[renovate]

This PR contains the following updates:

Package	Change	Age	Confidence
tornado (source)	==6.5.4 → ==6.5.5

GitHub Vulnerability Alerts

GHSA-78cv-mqj4-43f7

Values passed to the domain, path, and samesite arguments of RequestHandler.set_cookie were not completely validated in versions of Tornado prior to 6.5.5. In particular, semicolons would be allowed, which could be used to inject attacker-controlled values for other cookie attributes.

CVE-2026-31958

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.

Tornado 6.5.5 introduces new limits on the size and complexity of multipart bodies, including a default limit of 100 parts per request. These limits are configurable if needed; see tornado.httputil.ParseMultipartConfig. It is also now possible to disable multipart/form-data parsing entirely if it is not required for the application.

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Release Notes

tornadoweb/tornado (tornado)

v6.5.5

Compare Source

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