multiparty: Denial of Service via Prototype Pollution leads to Uncaught Exception

高 7.5CVE-2026-8161 · GHSA-qxch-whhj-8956 · 12/05/2026 公開 · 17/06/2026 更新

要点

CVE-2026-8161 は multiparty (pillarjs), multiparty に影響する深刻度「高」 (CVSS 7.5) の脆弱性です。
今後30日間に悪用される確率（EPSS）：0.47%（全脆弱性の 41.0% より高い）。
対処：4.3.0 以降に更新してください。

パッケージ	影響を受けるバージョン	修正済みバージョン
multiparty pillarjs	`< 4.3.0`	`4.3.0`
multiparty npm	`< 4.3.0`	`4.3.0`

概要

Impact

[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 (e.g., __proto__, constructor, 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. Any service accepting multipart uploads via multiparty is affected.

Patches

Users should upgrade to [email protected] or higher.

Workarounds

None.

NVD の説明

[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.