Medium severity · published Oct 14, 2021
CVE-2021-22963
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:…
6.1
CVSS
1.2%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)1.2% · higher than 67% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FA
Fastify-static · Fastify
before 4.2.4 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-22963
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-22963
Exploit
https://hackerone.com/reports/1354255
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