Medium severity · published Dec 1, 2025
CVE-2025-66415
fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server
5.4
CVSS
0.2%
EPSS
No
On KEV
Description
fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server. Prior to 12.5.0, by crafting a malicious URL, an attacker could access routes that are not allowed, even though the reply.from is defined for specific routes in @fastify/reply-from. This vulnerability is fixed in 12.5.0.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
RE
Reply-from · Fastify
through 12.4.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66415
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-66415
Patch
https://github.com/fastify/fastify-reply-from/commit/4d9795cd5b57a36756d37b7f036eae369f69fa66
Vendor Advisory
https://github.com/fastify/fastify-reply-from/security/advisories/GHSA-2q7r-29rg-6m5h
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7.5
CVE-2023-51701
fastify-reply-from is a Fastify plugin to forward the current HTTP request to another server