Fastify vulnerable to invalid content-type parsing, which could lead to validation bypass
Impact
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?
Software afectado
Haz clic en una tecnología para ver todas sus vulnerabilidades.
| Plataforma | Paquete | Versiones vulnerables | Corregida en |
|---|---|---|---|
| Paquete de npm | fastify | >= 5.0.0, < 5.3.2, >= 4.29.0, < 4.29.1 | 5.3.2, 4.29.1 |
Referencias
- https://github.com/fastify/fastify/security/advisories/GHSA-247c-9743-5963
- https://github.com/fastify/fastify/security/advisories/GHSA-mg2h-6x62-wpwc
- https://nvd.nist.gov/vuln/detail/CVE-2025-32442
- https://nvd.nist.gov/vuln/detail/CVE-2026-33806
- https://github.com/fastify/fastify/commit/f3d2bcb3963cd570a582e5d39aab01a9ae692fe4
- https://cna.openjsf.org/security-advisories.html
- https://github.com/fastify/fastify
- https://github.com/fastify/fastify/releases/tag/v5.8.5
- https://github.com/fastify/fastify/commit/436da4c06dfbbb8c24adee3a64de0c51e4f47418
- https://hackerone.com/reports/3087928
- Vector CVSS
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N- Debilidad (CWE)
CWE-1287- Plataforma
- npm
- Paquete
fastify- Publicada
- 18.04.2025
- Actualizado
- 11.10.2026 10:22
Fuentes y licencias
OSV / GitHub Advisory Database - GHSA-247c-9743-5963 - CC BY 4.0
OSV / GitHub Advisory Database - GHSA-mg2h-6x62-wpwc - CC BY 4.0
Historial de vulnerabilidades: fastify
Todas las vulnerabilidades publicadas de este paquete (Paquete de npm), de la más reciente a la más antigua. Muestra si es un fallo aislado o un paquete que hay que vigilar.
- Entradas en total
- 16
- Primera → última
- 07.2018 09.2026
- Sin corrección
- 0
- Explotada en ataques
- 0
Distribución por gravedad
- Alta 8
- Media 7
- Baja 1
Divulgaciones por año
- 2018: 1
- 2019: 0
- 2020: 1
- 2021: 0
- 2022: 2
- 2023: 0
- 2024: 0
- 2025: 1
- 2026: 11
-
Fastify vulnerable to invalid content-type parsing, which could lead to validation bypass esta entrada
Identifica las vulnerabilidades de tu aplicación
Con la integración de DockRay y el inventario de software activado, DockRay compara las versiones notificadas de los componentes con las vulnerabilidades conocidas y avisa de las coincidencias confirmadas. La cobertura depende de la tecnología compatible y de los avisos disponibles.