CVE-2026-8161

What it is

[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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.5% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-12 10:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-17 11:03 UTC Last updatedMost recent change to the record

Details

Published

2026-05-12 10:16 UTC

Last modified

2026-06-17 11:03 UTC

Exploit probability

0.5% · EPSS, next 30 days

Weakness

CWE-248

Record status

Analyzed

Affected

• Pillarjs Multiparty < 4.3.0

Attack profile CVSS 3.1 · 7.5

Attack vector

Network

Complexity

Low

Privileges needed

None

User interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High