---
cve: "CVE-2021-29624"
severity: "MEDIUM"
cvss: 6.5
epss: "83%"
vendor: "fastify"
kev: false
exploited: false
published: "2021-05-19 22:15:07"
tags: [cve, security, medium]
source: tsecurity.de CVE-Dossier
exported: "2026-09-07T12:08:13+02:00"
---

# CVE-2021-29624

> 6.5 MEDIUM · 🧪 PoC

## Beschreibung

fastify-csrf is an open-source plugin helps developers protect their Fastify server against CSRF attacks. Versions of fastify-csrf prior to 3.1.0 have a "double submit" mechanism using cookies with an application deployed across multiple subdomains, e.g. "heroku"-style platform as a service. Version 3.1.0 of the fastify-csrf fixes it. the vulnerability. The user of the module would need to supply a `userInfo` when generating the CSRF token to fully implement the protection on their end. This is needed only for applications hosted on different subdomains.

## CVSS-Vektor

```
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
```

| Metrik | Wert | Bewertung |
|---|---|---|
| AV Angriffsvektor | Netzwerk | bad |
| AC Komplexität | Gering | bad |
| PR Privilegien | Keine | bad |
| UI Interaktion | Erforderlich | good |
| S Scope | Unverändert | good |
| C Vertraulichkeit | Keine | good |
| I Integrität | Hoch | bad |
| A Verfügbarkeit | Keine | good |

## Patch verfügbar (OSV)

- 04d05fb613817cb8c723893c241820e1633881a4 (Commit)

## Referenzen

- <https://github.com/fastify/fastify-csrf/security/advisories/GHSA-rc4q-9m69-gqp8>
- <https://github.com/fastify/csrf/pull/2>
- <https://github.com/fastify/fastify-csrf/pull/51>
- <https://cheatsheetseries.owasp.org/cheatsheets/Cross-Site_Request_Forgery_Prevention_Cheat_Sheet.html>
- <https://github.com/fastify/fastify-csrf/releases/tag/v3.1.0>
- <https://owasp.org/www-pdf-archive/David_Johansson-Double_Defeat_of_Double-Submit_Cookie.pdf>

---
_Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2021-29624) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_