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CVE-2026-8161

Status: AnalyzedHigh (7.5)—

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.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vulnerabilidad en aplicación web expuesta (multiparty) que causa DoS por excepción no capturada; AV:N/PR:N/UI:N indica explotación remota sin autenticación. El impacto es degradación de disponibilidad, no ejecución de código.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Filter Network TrafficVulnerability ScanningPrivileged Account ManagementNetwork SegmentationLimit Access to Resource Over NetworkApplication Isolation and Sandboxing

Affected technologies (1)

Pillarjs — Multiparty

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2026-8161",
  "cveTags": [],
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  "lastModified": "2026-06-17T11:03:34.383",
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