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CVE PROGRAM SOURCE RECORD7.5 High

CVE-2026-54283

Starlette: request.form() limits silently ignored for application/x-www-form-urlencoded enable DoS

Description

Starlette is a lightweight ASGI framework/toolkit. From 0.4.1 until 1.3.1, request.form() accepts max_fields and max_part_size to bound resource consumption while parsing form data. These limits are enforced for multipart/form-data, but silently ignored for application/x-www-form-urlencoded. An unauthenticated attacker can therefore send a urlencoded body with an arbitrarily large number of fields or an arbitrarily large field, even when the application configured limits it believed would apply. This vulnerability is fixed in 1.3.1.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Kludex starlette

  • >= 0.4.1, < 1.3.1affected

References