CVE-2026-19484Patch(fastify / fastify\/busyboy)

LOWCVSS 7.5 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

  • Patch fastify fastify\/busyboy systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD 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.

0.5/ 10 priority

Sources & remediation

Weakness type (CWE)
CWE-835CWE-1322

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

NONE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

  • fastify\/busyboy

Threat summary

  • Patch or workaround signal is available
  • 1 mentions across 1 observed day

What's happening

  • Patch or workaround mentioned in 1 signal
  • Technical details provided in 1 signal
  • 1 total mentions across 1 day

Affected systems

Vendors
Products
fastify\/busyboy

Deep dive

Activity timeline1 mentions / 1d
00111Mentions · 2026-08-13: 1Patch / Workaround · 2026-08-13: 1Technical Details · 2026-08-13: 108-13
Signal classification1 categories
Patch
1100.0%
Referenced assets1 URL
By indicator
Full discourse1 post
  • Ulises Gascón@kom_256
    Patch

    🚨 High-severity security fix in @fastify/busboy@3.2.1 just released! Patches CVE-2026-19484: @fastify/busboy vulnerable to denial of service via oversized multipart boundary https://github.com/fastify/busboy/security/advisories/GHSA-xjh9-v7x6-24jw

    Post summary

    Fastify’s busboy 3.2.1 patch fixes CVE‑2026‑19484, a denial‑of‑service vulnerability caused by oversized multipart boundaries, with the advisory providing the fix details.

    11030357
    5.5K followersView on X
CPE platform detail1 entries

1 of 1 entries

PartVendorProductVersionTarget SWTarget HW
Appfastifyfastify\/busyboy-node.js-

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