Vulnerability 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.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Encode | Starlette | >= 0.4.1, < 1.3.1 |
Related Weaknesses (CWE)
References
- https://github.com/Kludex/starlette/security/advisories/GHSA-82w8-qh3p-5jfqMitigationVendor Advisory
FAQ
What is CVE-2026-54283?
CVE-2026-54283 is a vulnerability with a CVSS score of 7.5 (HIGH). 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 e...
How severe is CVE-2026-54283?
CVE-2026-54283 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-54283?
Check the references section above for vendor advisories and patch information. Affected products include: Encode Starlette.