CVE-2026-72574

A host header injection vulnerability in picocms/Pico through 2.1.4 allows an unauthenticated remote attacker to control the origin of JavaScript and CSS assets loaded by the default theme. When base_url is unset (the default), Pico::getBaseUrl in lib/Pico.php builds the base URL from unvalidated Host, X-Forwarded-Host, X-Forwarded-Proto, and X-Forwarded-Port request headers.

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

• https://github.com/picocms/Pico
• https://github.com/picocms/Pico/blob/master/lib/Pico.php
• https://picocms.org