CVE-2026-59989: Phalcon Cphalcon

Critical severity, CVSS 9.2. EPSS: 0.5% chance of exploitation in the next 30 days.

Phalcon is a high-performance, full-stack PHP framework. In 5.15.0 and earlier, resolveFilter in phalcon/Mvc/View/Engine/Volt/Compiler.zep builds the join filter by inserting the raw separator and array token values into generated PHP without passing them through expression(). An attacker who can influence Volt template source can place quote-breaking content in a join argument, inject PHP into the compiled cache file, and execute it when Phalcon\Mvc\View\Engine\Volt::render() loads the template. This issue is fixed in version 5.16.0.

Affected products

• Phalcon Cphalcon: before 5.16.0 (fixed in 5.16.0)

Published 2026-08-21. Last modified 2026-09-30.