CVE-2026-87908
An unauthenticated attacker can send a single request whose part carries a very large volume of header bytes, forcing the parser to buffer all of them and exhausting the process memory, which crashes the server.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.30%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
multiparty is a Node.js library for parsing multipart/form-data request bodies. In versions from 2.1.0 up to but not including 4.3.1, the parser does not bound the amount of memory used while accumulating the headers of a single multipart part. An unauthenticated attacker can send a single request whose part carries a very large volume of header bytes, forcing the parser to buffer all of them and exhausting the process memory, which crashes the server. This is a denial of service with no confidentiality or integrity impact. The issue is fixed in multiparty 4.3.1, which caps the size of the accumulated part headers. Users should upgrade to multiparty 4.3.1 or later.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.30% probability · 22th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400, CWE-770
- Source
- ce714d77-add3-4f53-aff5-83d477b104bb
References
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.