Topic
CVE-2026-109619
Critical PHP Vulnerabilities CVE-2026-109618 and CVE-2026-109619 Enable Unauthenticated Remote Code Execution
Vulnerabilities & Exploits
Mitigating PHP2Shell RCE Vulnerabilities CVE-2026-109618 and CVE-2026-109619 on Legacy PHP 5.6 Stacks with Varnish, Docker and Apache mod_php
Vulnerabilities & ExploitsPHP Foundation Reveals Two Critical RCE Vulnerabilities Fixed After 2024 Discovery Delays
Vulnerabilities & ExploitsCISA Urges Immediate Patching of Critical PHP Remote Code Execution Vulnerabilities
The U.S. Cybersecurity and Infrastructure Security Agency (CISA) has issued an urgent advisory regarding two severe vulnerabilities in the PHP programming language that allow unauthenticated remote code execution. Identified as CVE-2026-109618 and CVE-2026-109619, the flaws affect all environments processing web requests with PHP and have been nicknamed php2shell. CISA recommends applying patches to PHP 8.5.12, 8.4.27, 8.3.36, or 8.2.35 without delay, or taking affected systems offline if updates cannot be applied immediately. Although no exploitation has been observed yet, organizations are instructed to inventory PHP usage, prioritize internet-facing systems, and monitor for suspicious activity such as shell processes spawned from PHP workers. Web application firewalls may offer partial protection but are not considered a substitute for patching.
PHP Issues Emergency Patches for Critical PHP2Shell RCE Flaws as Exploit Attempts Emerge
PHP has released urgent patches for two critical vulnerabilities collectively known as PHP2Shell that enable unauthenticated remote code execution on affected servers. The flaws, tracked as CVE-2026-109618 and CVE-2026-109619, score 9.2 on CVSS v4.0 and have already seen active exploitation attempts with malicious payloads adjusted to bypass WAF rules. The issues affect multiple PHP deployment methods including Apache with mod_php, PHP-FPM, php-cgi, FrankenPHP, and LiteSpeed, and do not require complex application code to be exploitable. CVE-2026-109618 involves a memory corruption chain leading to code execution under the web process privileges, while CVE-2026-109619 stems from an obsolete global state issue causing use-after-free conditions that can result in memory disclosure and code execution. Patched versions include PHP 8.5.12, 8.4.27, 8.3.36, and 8.2.35, with administrators advised to restart all persistent workers after updating. Temporary mitigations such as setting memory_limit to -1 and disabling session.upload_progress.enabled are available for environments that cannot patch immediately.
Two Critical RCE Vulnerabilities Patched in PHP with CVSS 9.2 Scores
The PHP development team has disclosed two severe remote code execution vulnerabilities affecting the widely used scripting language. Both issues, tracked as CVE-2026-109618 and CVE-2026-109619, received a CVSSv4.0 base score of 9.2 and were rated Critical. The flaws stem from improper memory handling during request processing and cleanup phases. Exploitation could allow attackers to execute arbitrary code by manipulating uninitialized or residual data in worker processes. Security updates addressing both vulnerabilities were released on October 21, 2026, and users are strongly urged to apply the patches immediately. The advisories were previewed the previous day, highlighting the urgency of the fixes.
Critical PHP Core Flaws Enable Unauthenticated Remote Code Execution
The PHP project released emergency patches on October 21 for two critical vulnerabilities in the language core, tracked as CVE-2026-109618 and CVE-2026-109619 and collectively referred to as PHP2Shell. Both issues received a CVSS 4.0 score of 9.2 and allow remote code execution without authentication. CVE-2026-109618 resides in memory-handling routines where longjmp can leave request data partially initialized, and subsequent shutdown operates on invalid data; multipart requests with many headers or empty file fields can trigger the condition. CVE-2026-109619 affects an obsolete global state in long-lived workers that retain references to freed memory, with confirmed paths involving fatal errors, error reporting data, and session upload progress. Researchers demonstrated unauthenticated code execution over HTTP against the first flaw on Apache with mod_php using default limits, while PHP-FPM exposure was identified through code analysis. The FBI Cyber Division issued an alert urging immediate updates, and Cloudflare deployed WAF rules while confirming early attacks in the wild.