What is CVE-2026-8161?

CVE-2026-8161 is a high-severity vulnerability in Multiparty, classified under CWE-248. CVSS score: 7.5/10. Published 2026-05-12.

How severe is CVE-2026-8161?

High severity. CVSS v3 base score is 7.5 out of 10.

Is CVE-2026-8161 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Prototype Pollution in Multiparty

CVE-2026-8161

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__, constru…

EPSS: 0.000 (4.0th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Multiparty — versions 0, 4.3.0
Pillarjs Multiparty

Weakness classification (CWE)

Public proof-of-concept exploits

Ser0n-ath/multiparty-CVE-2026-8161

References

ce714d77-add3-4f53-aff5-83d477b104bb (Vendor Advisory)
ce714d77-add3-4f53-aff5-83d477b104bb (Third Party Advisory)

Frequently asked questions

What is CVE-2026-8161?: CVE-2026-8161 is a high-severity vulnerability in Multiparty, classified under CWE-248. CVSS score: 7.5/10. Published 2026-05-12.
How severe is CVE-2026-8161?: High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2026-8161 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.