# CVE-2023-30798: MultipartParser DOS with too many fields or files in Starlette Framework

Status: published. Published: 2023-04-21. Updated: 2026-11-08.

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.

## Remediation

- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: CNA: VulnCheck) — https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938fa
- fix: The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches. (source: ADP: CVE) — https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938fa
- fix: starlette (PyPI): OSV reports a fixed version 0.25.0. Check the advisory for supported release branches. (source: OSV GHSA-74m5-2c7w-9w3x) — https://github.com/advisories/GHSA-74m5-2c7w-9w3x

## Affected products and versions

- Encode / Starlette (starlette): ≥ 0; < 0.25.0 (affected, python). Source: CNA: VulnCheck; platforms: all
-  / starlette (starlette): 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: OSV GHSA-74m5-2c7w-9w3x

## Severity and prioritization

- CVSS 3.1: 7.5 (high); CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: 1.30% as of 2026-11-08; percentile 70.60%

- SSVC: exploitation none; automatable yes; technical impact partial; source ADP: CISA-ADP

- Weaknesses: CWE-400

## 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-9w3x (CNA: VulnCheck; vendor-advisory)

- https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938fa (CNA: VulnCheck; patch)

- https://vulncheck.com/advisories/starlette-multipartparser-dos (CNA: VulnCheck; third-party-advisory)

- https://github.com/encode/starlette/security/advisories/GHSA-74m5-2c7w-9w3x (ADP: CVE; vendor-advisory, x_transferred)

- https://github.com/encode/starlette/commit/8c74c2c8dba7030154f8af18e016136bea1938fa (ADP: CVE; patch, x_transferred)

- https://vulncheck.com/advisories/starlette-multipartparser-dos (ADP: CVE; third-party-advisory, x_transferred)

- https://github.com/advisories/GHSA-74m5-2c7w-9w3x (OSV / GitHub Security Advisories; advisory)

- https://osv.dev/vulnerability/GHSA-74m5-2c7w-9w3x (OSV / GitHub Security Advisories; osv)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2023-30798; retrieved 2026-11-08; source updated 2026-11-08

- OSV / GitHub Security Advisories: https://osv.dev/vulnerability/GHSA-74m5-2c7w-9w3x; retrieved 2026-11-08; source updated 2026-07-08

- FIRST EPSS: https://api.first.org/data/v1/epss?cve=CVE-2023-30798; retrieved 2026-11-08; source updated Not reported

Revision: abc4f1a4fdbdac635768b3d8fb7c7e3afc8a8554275d6df65f7721c65ed7e5ec

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