Description
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.
References3
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - EPSS — exploit probability
- 0% percentile: 37 · as of 12 November 2026
- CWE
- CWE-644
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.