Two critical vulnerabilities have been identified in PHP, a widely used programming language that powers websites and web applications. These vulnerabilities (CVE-2026-109618 and CVE-2026-109619) could allow malicious cyber actors to remotely execute code in PHP core, potentially compromising sensitive data and networks. The FBI urges organizations to take the following steps now: ➡️ If an immediate update is not feasible it is recommended that organizations take the system offline until it can be fully mitigated. ➡️ Immediately update affected PHP installations following the guidance on https://t.co/rDrPSxB3zX. Inventory where PHP runs in your environment, prioritizing internet-facing systems and vendor products that bundle PHP. ➡️ Monitor web servers for suspicious activity, including PHP processes unexpectedly launching command shells or downloading files. Ensure appropriate process-monitoring capabilities are in place to help identify potential exploitation. ➡️ If you find signs of compromise, isolate affected systems, preserve your web server and PHP logs, and report it to your local FBI field office or https://t.co/iqgVZIbCru. Those reports help us identify the actors involved and warn other organizations before they become victims. For the latest information, follow PHP’s announcement on https://t.co/rDrPSxB3zX, CERT-EU Security Advisory 2026-018, and CISA’s Known Exploited Vulnerabilities catalog.
— FBI Cyber Division (@FBICyberDiv) October 21, 2026