CVE-2026-117531
Full vulnerability record from the local CVENow database.
Description
@fastify/multipart is the multipart form-data and file upload plugin for the Fastify web framework. In versions 5.3.0 through 10.1.6, the plugin does not propagate a parser error to the file stream when a request body ends inside a file part with no closing boundary, even though the Content-Length is complete, the client does not abort, and no file size limit is exceeded. The plugin destroys the in-progress file stream without an error, so a handler that iterates the request parts and performs asynchronous work before consuming the file attaches to a stream that never emits an error or end event, and the request never responds while the connection stays open. An unauthenticated remote client can repeat these malformed uploads against such a route to accumulate pending connections and exhaust server resources, so the impact is availability only and exploitation depends on the application using a delayed file consumer. The issue is fixed in @fastify/multipart 10.1.7, where the parser error is propagated to the file stream so a delayed consumer settles with an error instead of hanging, and users should upgrade to 10.1.7 or later. There is no workaround other than upgrading.
View original CVE JSON
{
"id": "CVE-2026-117531",
"sourceIdentifier": "ce714d77-add3-4f53-aff5-83d477b104bb",
"published": "2026-11-02T11:17:30.853",
"lastModified": "2026-11-02T11:17:30.853",
"vulnStatus": "Received",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "@fastify/multipart is the multipart form-data and file upload plugin for the Fastify web framework. In versions 5.3.0 through 10.1.6, the plugin does not propagate a parser error to the file stream when a request body ends inside a file part with no closing boundary, even though the Content-Length is complete, the client does not abort, and no file size limit is exceeded. The plugin destroys the in-progress file stream without an error, so a handler that iterates the request parts and performs asynchronous work before consuming the file attaches to a stream that never emits an error or end event, and the request never responds while the connection stays open. An unauthenticated remote client can repeat these malformed uploads against such a route to accumulate pending connections and exhaust server resources, so the impact is availability only and exploitation depends on the application using a delayed file consumer. The issue is fixed in @fastify/multipart 10.1.7, where the parser error is propagated to the file stream so a delayed consumer settles with an error instead of hanging, and users should upgrade to 10.1.7 or later. There is no workaround other than upgrading."
}
],
"affected": [
{
"source": "ce714d77-add3-4f53-aff5-83d477b104bb",
"affectedData": [
{
"vendor": "@fastify/multipart",
"product": "@fastify/multipart",
"defaultStatus": "unaffected",
"packageURL": "pkg:npm/@fastify/multipart",
"versions": [
{
"version": "5.3.0",
"lessThan": "10.1.7",
"versionType": "semver",
"status": "affected"
},
{
"version": "10.1.7",
"versionType": "semver",
"status": "unaffected"
}
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "ce714d77-add3-4f53-aff5-83d477b104bb",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
"baseScore": 5.9,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.2,
"impactScore": 3.6
}
]
},
"weaknesses": [
{
"source": "ce714d77-add3-4f53-aff5-83d477b104bb",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-400"
}
]
}
],
"references": [
{
"url": "https://cna.openjsf.org/security-advisories.html",
"source": "ce714d77-add3-4f53-aff5-83d477b104bb"
},
{
"url": "https://github.com/fastify/fastify-multipart/security/advisories/GHSA-5849-5m6q-9632",
"source": "ce714d77-add3-4f53-aff5-83d477b104bb"
}
]
}