Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attacker fully controls boundary length in their own request, so AC:L; no authentication per PR:N; only availability impacted.
Primary rating from Vendor (openjs).
CVSS VectorVendor: openjs
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Lifecycle Timeline
3DescriptionCVE.org
@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.
Articles & Coverage 2
AnalysisAI
CPU exhaustion in @fastify/busboy 3.1.0-3.2.0 allows a remote unauthenticated attacker to stall the Node.js event loop by sending a single crafted multipart request. The parser's vendored streaming search algorithm stores its Boyer-Moore-style skip table in a fixed 256-entry byte array; supplying a boundary of exactly 252 bytes causes the computed search needle to reach 256 bytes, collapsing the skip distance to zero and converting an O(n) search into an unbounded CPU-bound loop. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | The application must be accepting HTTP multipart/form-data POST requests - meaning it must expose at least one route that parses request bodies using @fastify/busboy 3.1.0 through 3.2.0. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | The CVSS 3.1 vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H accurately reflects the attack surface: no authentication, no special preconditions beyond a reachable multipart endpoint, and high availability impact. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | An attacker sends a single HTTP POST request to any endpoint served by the vulnerable application that accepts multipart/form-data input, setting the Content-Type boundary parameter to a string of exactly 252 bytes and including a minimal body. The @fastify/busboy parser begins scanning for the boundary marker, computes a zero skip distance due to the table truncation bug, and enters a CPU-bound spin loop. … |
| Remediation | The primary fix is to upgrade @fastify/busboy to version 3.2.1, which widens the internal skip table so that the skip distance is correctly preserved regardless of boundary length. … Detailed patch versions, workarounds, and compensating controls in full report. |
Recommended ActionAI
Within 24 hours: inventory all deployments running @fastify/busboy 3.1.0-3.2.0 and classify affected services by criticality. …
Sign in for detailed remediation steps and compensating controls.
Threat intelligence, references, and detailed analysis are available after sign-in.
A vulnerability in the NuPoint Unified Messaging (NPM) component of Mitel MiCollab through 9.8 SP1 FP2 (9.8.1.201) could
FortiOS and FortiProxy contain an authentication bypass via the Node.js websocket module allowing unauthenticated remote
Eval injection vulnerability in the internals.batch function in lib/batch.js in the bassmaster plugin before 1.5.2 for t
Flowise version 3.0.5 contains a remote code execution vulnerability in the CustomMCP node. The mcpServerConfig paramete
Node.js 8.5.0 before 8.6.0 allows remote attackers to access unintended files, because a change to ".." handling was inc
An issue was discovered in the node-serialize package 0.0.4 for Node.js. Rated critical severity (CVSS 9.8), this vulner
Directory traversal vulnerability in the st module before 0.2.5 for Node.js allows remote attackers to read arbitrary fi
Multiple SQL injection vulnerabilities in the Manage Accounts page in the AccountManagement.asmx service in the Solarwin
The JS-YAML module before 2.0.5 for Node.js parses input without properly considering the unsafe !!js/function tag, whic
Directory traversal vulnerability in lib/app/index.js in Geddy before 13.0.8 for Node.js allows remote attackers to read
Credential-harvesting malware compromised 84 versions of 42 TanStack npm packages on 2026-05-11 via chained GitHub Actio
Eval injection vulnerability in index.js in the syntax-error package before 1.1.1 for Node.js 0.10.x, as used in IBM Rat
Same technique Denial Of Service
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-57759