multiparty vulnerable to Denial of Service via Prototype Pollution leading to Uncaught Exception
Title source: cnaExploitation Summary
EIP tracks 1 public exploit for CVE-2026-8161. PoCs published by Ser0n-ath.
AI-analyzed exploit summary This repository contains a functional proof-of-concept for CVE-2026-8161, a denial-of-service vulnerability in the `multiparty` library (versions 4.2.3 and earlier) caused by prototype pollution leading to uncaught exceptions during multipart form parsing. The PoC includes a Dockerized environment with vulnerable and patched servers, along with a Python script to trigger the crash.
Description
[email protected] and lower versions are vulnerable to denial of service via uncaught exception. By sending a multipart/form-data request with a field name that collides with an inherited Object.prototype property such as __proto__, constructor, or toString, the parser invokes .push() on the inherited prototype value rather than an array, throwing a TypeError that propagates as an uncaught exception and crashes the process. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: none. Upgrade to [email protected] or higher.
Exploits (1)
This repository contains a functional proof-of-concept for CVE-2026-8161, a denial-of-service vulnerability in the `multiparty` library (versions 4.2.3 and earlier) caused by prototype pollution leading to uncaught exceptions during multipart form parsing. The PoC includes a Dockerized environment with vulnerable and patched servers, along with a Python script to trigger the crash.
References (2)
Scores
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H