GHSA-MG2H-6X62-WPWC
Vulnerability from github – Published: 2025-04-18 15:02 – Updated: 2025-05-29 21:04Impact
In applications that specify different validation strategies for different content types, it's possible to bypass the validation by providing a slightly altered content type such as with different casing or altered whitespacing before ;.
Users using the the following pattern are affected:
fastify.post('/', {
handler(request, reply) {
reply.code(200).send(request.body)
},
schema: {
body: {
content: {
'application/json': {
schema: {
type: 'object',
properties: {
'foo': {
type: 'string',
}
},
required: ['foo']
}
},
}
}
}
})
User using the following pattern are not affected:
fastify.post('/', {
handler(request, reply) {
reply.code(200).send(request.body)
},
schema: {
body: {
type: 'object',
properties: {
'foo': {
type: 'string',
}
},
required: ['foo']
}
}
})
Patches
This was patched in v5.3.1, but unfortunately it did not cover all problems. This has been fully patched in v5.3.2. Version v4.9.0 was also affected by this issue. This has been fully patched in v4.9.1.
Workarounds
Do not specify multiple content types in the schema.
References
Are there any links users can visit to find out more?
https://hackerone.com/reports/3087928
{
"affected": [
{
"database_specific": {
"last_known_affected_version_range": "\u003c= 5.3.1"
},
"package": {
"ecosystem": "npm",
"name": "fastify"
},
"ranges": [
{
"events": [
{
"introduced": "5.0.0"
},
{
"fixed": "5.3.2"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "npm",
"name": "fastify"
},
"ranges": [
{
"events": [
{
"introduced": "4.29.0"
},
{
"fixed": "4.29.1"
}
],
"type": "ECOSYSTEM"
}
],
"versions": [
"4.29.0"
]
}
],
"aliases": [
"CVE-2025-32442"
],
"database_specific": {
"cwe_ids": [
"CWE-1287"
],
"github_reviewed": true,
"github_reviewed_at": "2025-04-18T15:02:41Z",
"nvd_published_at": "2025-04-18T16:15:23Z",
"severity": "HIGH"
},
"details": "### Impact\n\nIn applications that specify different validation strategies for different content types, it\u0027s possible to bypass the validation by providing a _slightly altered_ content type such as with different casing or altered whitespacing before `;`.\n\nUsers using the the following pattern are affected:\n\n```js\nfastify.post(\u0027/\u0027, {\n handler(request, reply) {\n reply.code(200).send(request.body)\n },\n schema: {\n body: {\n content: {\n \u0027application/json\u0027: {\n schema: {\n type: \u0027object\u0027,\n properties: {\n \u0027foo\u0027: {\n type: \u0027string\u0027,\n }\n },\n required: [\u0027foo\u0027]\n }\n },\n }\n }\n }\n})\n```\n\nUser using the following pattern are **not** affected:\n\n```js\nfastify.post(\u0027/\u0027, {\n handler(request, reply) {\n reply.code(200).send(request.body)\n },\n schema: {\n body: {\n type: \u0027object\u0027,\n properties: {\n \u0027foo\u0027: {\n type: \u0027string\u0027,\n }\n },\n required: [\u0027foo\u0027]\n }\n }\n})\n```\n\n### Patches\n\nThis was patched in v5.3.1, but unfortunately it did not cover all problems. This has been fully patched in v5.3.2.\nVersion v4.9.0 was also affected by this issue. This has been fully patched in v4.9.1.\n\n### Workarounds\n\nDo not specify multiple content types in the schema.\n\n### References\n_Are there any links users can visit to find out more?_\n\nhttps://hackerone.com/reports/3087928",
"id": "GHSA-mg2h-6x62-wpwc",
"modified": "2025-05-29T21:04:54Z",
"published": "2025-04-18T15:02:41Z",
"references": [
{
"type": "WEB",
"url": "https://github.com/fastify/fastify/security/advisories/GHSA-mg2h-6x62-wpwc"
},
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2025-32442"
},
{
"type": "WEB",
"url": "https://github.com/fastify/fastify/commit/436da4c06dfbbb8c24adee3a64de0c51e4f47418"
},
{
"type": "WEB",
"url": "https://github.com/fastify/fastify/commit/f3d2bcb3963cd570a582e5d39aab01a9ae692fe4"
},
{
"type": "WEB",
"url": "https://hackerone.com/reports/3087928"
},
{
"type": "PACKAGE",
"url": "https://github.com/fastify/fastify"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
"type": "CVSS_V3"
}
],
"summary": "Fastify vulnerable to invalid content-type parsing, which could lead to validation bypass"
}
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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