CVE-2026-19484

Public on 2026-08-13
Modified on 2026-08-19
Description
@fastify/busboy is a multipart form-data parser. In versions 3.1.0 through 3.2.0, a remote unauthenticated attacker can stall the Node.js event loop by sending a multipart request whose boundary is crafted to a specific length. The vendored streaming search stores its skip table in a fixed 256 entry byte array, and a boundary of exactly 252 bytes makes the search needle 256 bytes, which truncates the default skip distance to zero and turns the search into a CPU bound loop on a small body. A single small request can keep one core busy and deny service to other requests handled by the same process. The issue is fixed in @fastify/busboy 3.2.1, which widens the skip table so the skip distance is preserved. Users should upgrade to 3.2.1.
Severity
Important severity
Important
See what this means
CVSS v3 Base Score
7.5
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 2023 nodejs20 No Fix Planned
Amazon Linux 2023 nodejs22 Not Affected
Amazon Linux 2023 nodejs24 Not Affected

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H