PT-2026-39996 · Npm · Multipart

Aszx87410 + 2 · CVE-2026-8159 · Published 2026-05-12 · Updated 2026-07-14

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions multiparty versions prior to 4.3.0

Description A denial of service issue exists due to regular expression backtracking in the Content-Disposition filename parameter parser. A crafted multipart upload containing a long header value can cause regex matching to take several seconds, which blocks the event loop. This affects any service that accepts multipart uploads using this library.

Recommendations Upgrade to version 4.3.0 or higher. Limit upload sizes at the proxy or gateway layer to reduce the attack surface.

Exploit

Fix

DoS

Weakness Enumeration

CWE-1333

Related Identifiers

CVE-2026-8159

GHSA-65X3-RW7Q-GX94

Affected Products

Multipart

References · 18

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/8xxx/CVE-2026-8159.json · Exploit
• https://github.com/pillarjs/multiparty/security/advisories/GHSA-65x3-rw7q-gx94 · Vendor Advisory
• https://osv.dev/vulnerability/GHSA-65x3-rw7q-gx94 · Vendor Advisory
• https://osv.dev/vulnerability/ROOT-APP-NPM-CVE-2026-8159 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-8159 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-8159 · Security Note
• https://security-tracker.debian.org/tracker/CVE-2026-8159 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2026-8159 · Security Note
• https://ubuntu.com/security/CVE-2026-8159 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-8159 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-8159 · Vendor Advisory
• https://github.com/pillarjs/multiparty · Note
• https://github.com/pillarjs/multiparty/releases/tag/v4.3.0 · Note
• https://owasp.org/www-community/attacks/Regular_expression_Denial_of_Service_-_ReDoS · Note
• https://twitter.com/VulmonFeeds/status/2054225368823873930 · Twitter Post