high7.5
CVE-2026-8161
multiparty@4.2.3 and lower versions are vulnerable to denial of service via uncaught exception.
Impact
multiparty@4.2.3 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 multiparty@4.3.0 or higher.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| npm | multiparty | <= 4.2.3 | 4.3.0 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Pillarjs | Multiparty | before 4.3.0 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-qxch-whhj-8956
- https://github.com/pillarjs/multiparty/security/advisories/GHSA-qxch-whhj-8956
- https://nvd.nist.gov/vuln/detail/CVE-2026-8161
- https://cna.openjsf.org/security-advisories.html
- https://github.com/pillarjs/multiparty/releases/tag/v4.3.0