CVE-2023-30798

MultipartParser DOS with too many fields or files in Starlette Framework

publishedCWE-400

There MultipartParser usage in Encode's Starlette python framework before versions 0.25.0 allows an unauthenticated and remote attacker to specify any number of form fields or files which can cause excessive memory usage resulting in denial of service of the HTTP service.

Technical severity7.5 highCVSS 3.1 · CNA: VulnCheck

Published2023-04-21Source updated 2026-11-08

Collected2026-11-083 attributed sources

Fixes and workarounds

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: CNA: VulnCheck

Fix

The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.

Source: ADP: CVE

Fix

starlette (PyPI): OSV reports a fixed version 0.25.0. Check the advisory for supported release branches.

Source: OSV GHSA-74m5-2c7w-9w3x

Affected products and versions

Affected products, source version ranges and reporting authorities
Product	Versions	Authority
Starlette Encode `starlette` pypi Platforms: all	≥ 0; < 0.25.0 (affected, python) Other versions: unaffected	CNA: VulnCheck
starlette `starlette` PyPI	0.1.0 (affected, PyPI) 0.1.1 (affected, PyPI) 0.1.10 (affected, PyPI) 0.1.11 (affected, PyPI) 0.1.12 (affected, PyPI) 0.1.13 (affected, PyPI) 0.1.14 (affected, PyPI) 0.1.15 (affected, PyPI) 0.1.16 (affected, PyPI) 0.1.17 (affected, PyPI) 0.1.2 (affected, PyPI) 0.1.3 (affected, PyPI) 0.1.4 (affected, PyPI) 0.1.5 (affected, PyPI) 0.1.6 (affected, PyPI) 0.1.7 (affected, PyPI) 0.1.8 (affected, PyPI) 0.1.9 (affected, PyPI) 0.10.0 (affected, PyPI) 0.10.1 (affected, PyPI) 0.10.2 (affected, PyPI) 0.10.3 (affected, PyPI) 0.10.4 (affected, PyPI) 0.10.5 (affected, PyPI) 0.10.6 (affected, PyPI) 0.10.7 (affected, PyPI) 0.11.0 (affected, PyPI) 0.11.1 (affected, PyPI) 0.11.2 (affected, PyPI) 0.11.3 (affected, PyPI) 0.11.4 (affected, PyPI) 0.12.0 (affected, PyPI) 0.12.0b1 (affected, PyPI) 0.12.0b2 (affected, PyPI) 0.12.0b3 (affected, PyPI) 0.12.1 (affected, PyPI) 0.12.10 (affected, PyPI) 0.12.11 (affected, PyPI) 0.12.12 (affected, PyPI) 0.12.13 (affected, PyPI) 0.12.2 (affected, PyPI) 0.12.3 (affected, PyPI) 0.12.4 (affected, PyPI) 0.12.5 (affected, PyPI) 0.12.6 (affected, PyPI) 0.12.7 (affected, PyPI) 0.12.8 (affected, PyPI) 0.12.9 (affected, PyPI) 0.13.0 (affected, PyPI) 0.13.1 (affected, PyPI) 0.13.2 (affected, PyPI) 0.13.3 (affected, PyPI) 0.13.4 (affected, PyPI) 0.13.5 (affected, PyPI) 0.13.6 (affected, PyPI) 0.13.7 (affected, PyPI) 0.13.8 (affected, PyPI) 0.14.0 (affected, PyPI) 0.14.1 (affected, PyPI) 0.14.2 (affected, PyPI) 0.15.0 (affected, PyPI) 0.16.0 (affected, PyPI) 0.17.0 (affected, PyPI) 0.17.1 (affected, PyPI) 0.18.0 (affected, PyPI) 0.19.0 (affected, PyPI) 0.19.1 (affected, PyPI) 0.2.0 (affected, PyPI) 0.2.1 (affected, PyPI) 0.2.2 (affected, PyPI) 0.2.3 (affected, PyPI) 0.20.0 (affected, PyPI) 0.20.1 (affected, PyPI) 0.20.2 (affected, PyPI) 0.20.3 (affected, PyPI) 0.20.4 (affected, PyPI) 0.21.0 (affected, PyPI) 0.22.0 (affected, PyPI) 0.23.0 (affected, PyPI) 0.23.1 (affected, PyPI) 0.24.0 (affected, PyPI) 0.3.0 (affected, PyPI) 0.3.1 (affected, PyPI) 0.3.2 (affected, PyPI) 0.3.3 (affected, PyPI) 0.3.4 (affected, PyPI) 0.3.5 (affected, PyPI) 0.3.6 (affected, PyPI) 0.3.7 (affected, PyPI) 0.4.0 (affected, PyPI) 0.4.1 (affected, PyPI) 0.4.2 (affected, PyPI) 0.5.0 (affected, PyPI) 0.5.1 (affected, PyPI) 0.5.2 (affected, PyPI) 0.5.3 (affected, PyPI) 0.5.4 (affected, PyPI) 0.5.5 (affected, PyPI) 0.6.0 (affected, PyPI) 0.6.1 (affected, PyPI) 0.6.2 (affected, PyPI) 0.6.3 (affected, PyPI) 0.7.0 (affected, PyPI) 0.7.1 (affected, PyPI) 0.7.2 (affected, PyPI) 0.7.3 (affected, PyPI) 0.7.4 (affected, PyPI) 0.8.0 (affected, PyPI) 0.8.1 (affected, PyPI) 0.8.2 (affected, PyPI) 0.8.3 (affected, PyPI) 0.8.4 (affected, PyPI) 0.8.5 (affected, PyPI) 0.8.6 (affected, PyPI) 0.8.7 (affected, PyPI) 0.8.8 (affected, PyPI) 0.9.0 (affected, PyPI) 0.9.1 (affected, PyPI) 0.9.10 (affected, PyPI) 0.9.11 (affected, PyPI) 0.9.2 (affected, PyPI) 0.9.3 (affected, PyPI) 0.9.4 (affected, PyPI) 0.9.5 (affected, PyPI) 0.9.6 (affected, PyPI) 0.9.7 (affected, PyPI) 0.9.8 (affected, PyPI) 0.9.9 (affected, PyPI) Ecosystem version events: introduced 0; fixed 0.25.0 Source events (ECOSYSTEM) `[ { "introduced": "0" }, { "fixed": "0.25.0" } ]` Other versions: unaffected	OSV GHSA-74m5-2c7w-9w3x

Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.

CVSS assessments

CVSS scores, vectors and reporting authorities
Version / score	Vector	Authority
3.1 / 7.5 high	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`	CNA: VulnCheck

Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

References

https://github.com/encode/starlette/security/advisories/GHSA-74m5-2c7w-9w3xCNA: VulnCheck · vendor-advisory
https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938faCNA: VulnCheck · patch
https://vulncheck.com/advisories/starlette-multipartparser-dosCNA: VulnCheck · third-party-advisory
https://github.com/encode/starlette/security/advisories/GHSA-74m5-2c7w-9w3xADP: CVE · vendor-advisory, x_transferred
https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938faADP: CVE · patch, x_transferred
https://vulncheck.com/advisories/starlette-multipartparser-dosADP: CVE · third-party-advisory, x_transferred
https://github.com/advisories/GHSA-74m5-2c7w-9w3xOSV / GitHub Security Advisories · advisory
https://osv.dev/vulnerability/GHSA-74m5-2c7w-9w3xOSV / GitHub Security Advisories · osv

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