High severity · published Oct 14, 2021
CVE-2021-22964
A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double…
8.8
CVSS
1%
EPSS
No
On KEV
Description
A redirect vulnerability in the `fastify-static` module version >= 4.2.4 and < 4.4.1 allows remote attackers to redirect Mozilla Firefox users to arbitrary websites via a double slash `//` followed by a domain: `http://localhost:3000//a//youtube.com/%2e%2e%2f%2e%2e`.A DOS vulnerability is possible if the URL contains invalid characters `curl --path-as-is "http://localhost:3000//^/.."`The issue shows up on all the `fastify-static` applications that set `redirect: true` option. By default, it is `false`.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.0% · higher than 63% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FA
Fastify-static · Fastify
4.2.4 before 4.4.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22964
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22964
Exploit
https://hackerone.com/reports/1361804
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