Starlette is an Asynchronous Server Gateway Interface (ASGI) framework/toolkit. Prior to version 0.40.0, Starlette treats `multipart/form-data` parts without a `filename` as text form fields and buffers those in byte strings with no size limit. This allows an attacker to upload arbitrary large form fields and cause Starlette to both slow down significantly due to excessive memory allocations and copy operations, and also consume more and more memory until the server starts swapping and grinds to a halt, or the OS terminates the server process with an OOM error. Uploading multiple such requests in parallel may be enough to render a service practically unusable, even if reasonable request size limits are enforced by a reverse proxy in front of Starlette. This Denial of service (DoS) vulnerability affects all applications built with Starlette (or FastAPI) accepting form requests. Verison 0.40.0 fixes this issue.
History

Wed, 16 Oct 2024 01:30:00 +0000

Type Values Removed Values Added
References
Metrics threat_severity

None

threat_severity

Important


Tue, 15 Oct 2024 17:15:00 +0000

Type Values Removed Values Added
First Time appeared Encode
Encode starlette
CPEs cpe:2.3:a:encode:starlette:*:*:*:*:*:python:*:*
Vendors & Products Encode
Encode starlette
Metrics cvssV3_1

{'score': 0, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 15 Oct 2024 16:00:00 +0000

Type Values Removed Values Added
Description Starlette is an Asynchronous Server Gateway Interface (ASGI) framework/toolkit. Prior to version 0.40.0, Starlette treats `multipart/form-data` parts without a `filename` as text form fields and buffers those in byte strings with no size limit. This allows an attacker to upload arbitrary large form fields and cause Starlette to both slow down significantly due to excessive memory allocations and copy operations, and also consume more and more memory until the server starts swapping and grinds to a halt, or the OS terminates the server process with an OOM error. Uploading multiple such requests in parallel may be enough to render a service practically unusable, even if reasonable request size limits are enforced by a reverse proxy in front of Starlette. This Denial of service (DoS) vulnerability affects all applications built with Starlette (or FastAPI) accepting form requests. Verison 0.40.0 fixes this issue.
Title Starlette Denial of service (DoS) via multipart/form-data
Weaknesses CWE-770
References
Metrics cvssV4_0

{'score': 8.7, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published: 2024-10-15T15:45:03.555Z

Updated: 2024-11-21T16:53:01.345Z

Reserved: 2024-10-04T16:00:09.630Z

Link: CVE-2024-47874

cve-icon Vulnrichment

Updated: 2024-10-15T16:23:32.412Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2024-10-15T16:15:05.260

Modified: 2024-11-21T17:15:17.990

Link: CVE-2024-47874

cve-icon Redhat

Severity : Important

Publid Date: 2024-10-15T15:45:03Z

Links: CVE-2024-47874 - Bugzilla