What’s Vulnerable › Vulnerabilities
CVE-2021-22963
- Severity: medium (CVSS 6.1 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 1.2% probability of exploitation in the next 30 days
- Public exploit or detection template: yes
- Published: 2021-10-14 · updated 2026-06-17
- Weakness: CWE-601
Description
A redirect vulnerability in the fastify-static module version < 4.2.4 allows remote attackers to redirect users to arbitrary websites via a double slash // followed by a domain: http://localhost:3000//google.com/%2e%2e.The issue shows up on all the fastify-static applications that set redirect: true option. By default, it is false.
Affected products
- https://github.com/fastify/fastify-static: before 4.2.4 — fixed in 4.2.4
How to fix
Upgrade to a fixed version: https://github.com/fastify/fastify-static 4.2.4. Check the vendor advisory for mitigations.
References
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