High severity · published Jan 8, 2024
CVE-2023-51701
@fastify-reply-from JSON Content-Type parsing confusion
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. A reverse proxy server built with `@fastify/reply-from` could misinterpret the incoming body by passing an header `ContentType: application/json ; charset=utf-8`. This can lead to bypass of security checks. This vulnerability has been patched in '@fastify/reply-from` version 9.6.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FA
fastify-reply-from · fastify
< 9.6.0 · source: vendor
RE
Reply-from · Fastify
before 9.6.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2023-51701
CVE.org
https://www.cve.org/CVERecord?id=CVE-2023-51701
Release Notes
https://github.com/fastify/fastify-reply-from/releases/tag/v9.6.0
Vendor Advisory
https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-v2v2-hph8-q5xp
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10.0
CVE-2026-16158
@fastify/reply-from vulnerable to cross-upstream request routing via URL cache key collision
5.4
CVE-2025-66415
fastify-reply-from bypass of reply forwarding