CVE-2026-8161

Summary

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 Software

VendorProductVersion RangeStatus
multipartymultiparty0 <= 4.2.3affected
multipartymultiparty4.3.0unaffected

Weaknesses

  • CWE-248: CWE-248: Uncaught Exception
  • CWE-1321: CWE-1321: Improperly Controlled Modification of Object Prototype Attributes ('Prototype Pollution')

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: yes
    • Technical Impact: partial

References