CriticalCISAOct 21, 2026

Critical Vulnerabilities in PHP Require Immediate Patching

CISA strongly urges organizations to immediately patch the recently disclosed critical vulnerabilities in PHP, CVE-2026-109618 and CVE-2026-109619 . These vulnerabilities, known as “php2shell,” allow for unauthenticated remote code execution in PHP and affect all PHP installations serving web requests. Organizations should immediately update to PHP 8.5.12, 8.4.27, 8.3.36, or 8.2.35 to fix these vulnerabilities. While CISA has not observed exploitation of these vulnerabilities as of the time of publication, they pose a risk to organizations if left unpatched.  CISA urges organizations to take the following actions: Identify and inventory systems running any version of PHP across your org

Why it matters

The weakness can enable direct compromise with limited attacker prerequisites, making internet-facing assets the first place to look.

What defenders should do

Identify affected versions, prioritize internet-facing systems, and apply the vendor remediation.

Verify at the source

CyberKit curates and prioritizes; the source remains authoritative. Read the original advisory at www.cisa.gov →

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