CVE-2026-8159

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://cna.openjsf.org/security-advisories.html	Third Party Advisory
https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94	Mitigation Vendor Advisory
https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS	Not Applicable

Configurations

Configuration 1 (hide)

cpe:2.3:a:pillarjs:multiparty:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-05-12 10:16

Updated : 2026-06-17 11:03

NVD link : CVE-2026-8159

Mitre link : CVE-2026-8159

CVE.ORG link : CVE-2026-8159

JSON object : View

Products Affected

pillarjs

multiparty

CWE

CWE-1333

Inefficient Regular Expression Complexity

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