GHSA-65x3-rw7q-gx94HighCVSS 7.5

multiparty vulnerable to ReDoS via filename parsing

Published
May 18, 2026
Last Modified
May 18, 2026

🔗 CVE IDs covered (1)

📋 Description

Impact

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 multipart upload with a long header value containing !filename="1 repeated can cause regex matching to take seconds, blocking the event loop. Any service accepting multipart uploads via multiparty is affected.

Patches

Users should upgrade to multiparty@4.3.0 or higher.

Workarounds

None. Limiting upload sizes at the proxy/gateway layer reduces but does not eliminate the attack surface, since a small ~8 KB header is sufficient to trigger the vulnerable backtracking.

Resources

🎯 Affected products1

  • npm/multiparty:<= 4.2.3

🔗 References (6)