How severe is CVE-2023-51701?

CVE-2023-51701 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2023-51701 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-51701?

CVE-2023-51701 affects Fastify Reply-from. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-51701?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2023-51701 have an EU (EUVD) identifier?

Yes. CVE-2023-51701 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0427.

When was CVE-2023-51701 published?

CVE-2023-51701 was published on 2024-01-08 and last updated on 2026-06-17.

CVE-2023-51701

CVE-2023-51701 is a medium-severity vulnerability in Fastify Reply-from with a CVSS 3.x base score of 5.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-444.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (38th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0427
Weakness: CWE-444
Affected product: Fastify Reply-from
Published: 2024-01-08
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-51701?: 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.
How severe is CVE-2023-51701?: CVE-2023-51701 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2023-51701 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (38th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-51701?: CVE-2023-51701 affects Fastify Reply-from. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-51701?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2023-51701 have an EU (EUVD) identifier?: Yes. CVE-2023-51701 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0427.
When was CVE-2023-51701 published?: CVE-2023-51701 was published on 2024-01-08 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:fastify:reply-from:*:*:*:*:*:node.js:*:*

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