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TI-2023-28347 Aliases CVE-2023-51701GHSA-v2v2-hph8-q5xp

@fastify-reply-from JSON Content-Type parsing confusion

Priority LOW 39CWE-444Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00479 41st percentileScored 2026-11-07
Fix Fixed fastify-reply-from (fastify): 9.6.0@fastify/reply-from (npm): 9.6.0

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
fastifyfastify-reply-frombefore 9.6.09.6.0Patch availableCNA
—@fastify/reply-from (npm)before 9.6.09.6.0Patch availableGHSA-v2v2-hph8-q5xp
  • fastify-reply-from Vendorfastify Affected before 9.6.0 Fixed in 9.6.0 Patch available CNA
  • @fastify/reply-from (npm) Vendor— Affected before 9.6.0 Fixed in 9.6.0 Patch available GHSA-v2v2-hph8-q5xp

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:fastify:reply-from:*:*:*:*:*:node.js:*:*before 9.6.0Vulnerablefastify
  • cpe:2.3:a:fastify:reply-from:*:*:*:*:*:node.js:*:* Versions before 9.6.0 Vulnerable ·fastify

Remediation

  • Fix · CNA fastify-reply-from (fastify) Fixed in 9.6.0
  • Fix · GHSA-v2v2-hph8-q5xp @fastify/reply-from (npm) Fixed in 9.6.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-51701
  2. 2026-10-03 Alias added: GHSA-v2v2-hph8-q5xp

References

Advisory 2

Other 3

  • TI-2026-26177 @fastify/reply-from vulnerable to connection header abuse enabling stripping of proxy-added headers CVSS 4.0CRITICAL 9.0
  • TI-2025-40851 fastify-reply-from bypass of reply forwarding CVSS 4.0MEDIUM 6.9

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences