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.
Severity (CVSS)
| Base score | 7.5 |
|---|---|
| Severity | High |
| Version | CVSS 3.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| Provided by | CNA |
Weaknesses
- CWE-770 — CWE-770: Allocation of Resources Without Limits or Throttling
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Kludex | starlette | >= 0.4.1, < 1.3.1 |
References
- https://github.com/Kludex/starlette/security/advisories/GHSA-82w8-qh3p-5jfq (x_refsource_CONFIRM)
Generated from the official CVE List on 23 Jun 2026 10:05 UTC.