What is the CVSS score of CVE-2023-51701?

CVE-2023-51701 has a CVSS 3.1 base score of 5.3 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N. EPSS exploitation probability: 0.2%.

Which versions of Reply From are affected by CVE-2023-51701?

Organizations using fastify-reply-from should be aware of moderate risk from CVE-2023-51701 rated CVSS 5.3. Exploitation could compromise the security of affected deployments.. A patch is available.

How to fix or mitigate CVE-2023-51701?

Within 30 days: Identify affected systems and apply vendor patches as part of regular patch cycle. Monitor vendor channels for patch availability.

Reply From CVE-2023-51701

MEDIUM

HTTP Request/Response Smuggling (CWE-444)

2024-01-08 security-advisories@github.com

Request Smuggling Authentication Bypass Reply From

5.3

CVSS 3.1 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

5.3 MEDIUM

AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

Low

Integrity

None

Availability

None

Lifecycle Timeline

Patch released

Mar 31, 2026 - 21:13 nvd

Patch available

Analysis Generated

Mar 28, 2026 - 19:34 vuln.today

CVE Published

Jan 08, 2024 - 14:15 nvd

MEDIUM 5.3

DescriptionGitHub Advisory

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.

AnalysisAI

fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Rated medium severity (CVSS 5.3), this vulnerability is remotely exploitable, no authentication required, low attack complexity. This HTTP Request/Response Smuggling vulnerability could allow attackers to manipulate HTTP request interpretation between frontend and backend servers.

Technical ContextAI

This vulnerability is classified as HTTP Request/Response Smuggling (CWE-444), which allows attackers to manipulate HTTP request interpretation between frontend and backend servers. 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. Affected products include: Fastify Reply-From. Version information: version 9.6.0..

RemediationAI

A vendor patch is available. Apply the latest security update as soon as possible. Enforce strict HTTP parsing, normalize requests at proxy layer, use HTTP/2 end-to-end, reject ambiguous headers.