All vulnerabilities
CVE-2026-107318GHSA-j425-jw94-m29r

@fastify/reply-from vulnerable to improper certificate validation in built-in HTTPS transports

@fastify/reply-from @fastify/reply-fromFrameworks
CVSS
7.4High
ExploitationNo known exploitationNot in CISA KEV, which does not prove it is unexploitedCISA KEV
Exploit odds (EPSS)0.14%Chance of exploitation activity in the next 30 days, higher than 3% of CVEs. Scored 23 Oct 2026FIRST EPSS
Fixed in12.7.0Fixed versionCVE List
Published8 Oct 2026Updated 9 Oct 2026CVE List

What fixes it

  • 12.7.0@fastify/reply-fromCVE List
  • 12.7.0@fastify/reply-from, npmGitHubnpm install @fastify/reply-from@12.7.0

A fixed version on one release line is not the upgrade target for every line. Check your exact version and any vendor backports.

Description

@fastify/reply-from is a Fastify plugin that forwards requests to an upstream HTTP or HTTPS server. In versions prior to 12.7.0, all of the built-in HTTPS transports override the secure default and set rejectUnauthorized to false, so the proxy does not verify the TLS certificate of the upstream even when the application points it at an https upstream in the default configuration. An on-path network attacker can therefore impersonate the configured HTTPS upstream, read the credentials and request bodies the proxy forwards, and return forged responses that the application trusts. The issue is fixed in @fastify/reply-from 12.7.0, and users should upgrade to 12.7.0 or later. As a workaround, pass an explicit rejectUnauthorized true on the transport, supply an already configured undici instance, or use the undici global agent.

Text from CVE List

Affected versions 3

  • @fastify/reply-fromaffected: all versions before 12.7.0CVE List
  • @fastify/reply-fromunaffected: 12.7.0CVE List
  • @fastify/reply-from, npm< 12.7.0GitHub

References 2