VULNERABILITY INTELLIGENCE

CVE-2026-8159

CVSS score7.5 HIGH
EPSS probability0.34%
CISA KEVNot currently listed
Published2026-05-12
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

multiparty@4.2.3 and lower versions are vulnerable to denial of service via regular expression backtracking in the Content-Disposition filename parameter parser. A crafted multipart upload with a long header value can cause regex matching to take seconds, blocking the event loop. Impact: any service accepting multipart uploads via multiparty is affected. Workarounds: limiting upload sizes at the proxy or gateway layer reduces but does not eliminate the attack surface, since a small header of around 8 KB is sufficient to trigger the vulnerable backtracking. Upgrade to multiparty@4.3.0 or higher.

Weakness classification

  • ce714d77-add3-4f53-aff5-83d477b104bb: CWE-1333

Primary references