The Pulse
PHP Rushes Fixes After AI-Assisted Flaws Draw Exploit Attempts
PHP released fixes for two critical vulnerabilities after Amazon reported an exploitation attempt four days before public disclosure. The flaws affect web-facing PHP installations, and the project says updating is the only complete fix.
AI.info Team · Written with AI · fact-checked ·
An attempt appeared four days before disclosure
Amazon says its MadPot honeypot network recorded a PHP2Shell exploitation attempt on October 17, four days before PHP publicly disclosed the flaws and released fixes. The company traced the attempt to an IP address associated with a commercial anonymization network, but says it remains unclear how the actor obtained information about the vulnerabilities while they were under embargo.
PHP issued the updates on October 21, 2026, for two bugs that can enable unauthenticated remote code execution. Amazon later detected more attempts against its sensors, including activity after proof-of-concept exploits appeared following the public release. Its analysis had not established whether those attempts would have worked against real-world systems.
“There are no complete mitigations, updating is the only safe choice.”Daniel Scherzer, PHP development team
Two flaws reach into PHP’s request handling
The vulnerabilities, CVE-2026-109618 and CVE-2026-109619, affect PHP’s handling of memory and errors during web requests. In one flaw, an out-of-memory condition can leave internal request data only partly initialized; later cleanup may treat that invalid data as usable. In the other, internal state can outlive the memory it points to, allowing a later request handled by the same worker to use a stale reference.
PHP’s advisory says the risk covers web-facing installations, including PHP-FPM, Apache’s mod_php, php-cgi, FrankenPHP and LiteSpeed. It identifies mod_php as the highest-risk configuration, where researchers demonstrated an unauthenticated request could trigger an attack before application code runs. Wiz says its researchers demonstrated remote code execution on WordPress, Drupal and Joomla, while stressing that the vulnerability sits in PHP itself rather than in those applications.
AI helped researchers turn old bugs into working exploits
The flaws were reported by multiple researchers. The PHP Foundation says Calif began an audit of PHP on July 30 and reported an unauthenticated remote-code-execution path on August 11. OpenAI independently reported the same root cause, then reported further attack vectors on September 18; Wiz reported its findings on August 24. Wiz’s account says its researchers used Wiz Atlas, Gemini 4 Argon and GPT-5.6 Sol in their research.
The PHP Foundation says a core developer had noticed signs of the out-of-memory problem during work following a 2024 security audit, but researchers then lacked a concrete route to exploitation. The team struggled to settle on a fix because proposed approaches carried compatibility, denial-of-service or extension-maintenance costs. The Foundation says the reports clarified the full impact and moved the issue to the top of its security team’s priorities.
Wiz says its researchers chained multiple memory flaws and used AI tools to adapt and test the exploit across different application setups. The firm reports successful demonstrations against recent WordPress, Drupal and Joomla container images; that is evidence of exploitability in those test environments, not proof that every PHP site was compromised.
Updates are available, but older installations need care
PHP’s fixed releases are 8.5.12, 8.4.27, 8.3.36 and 8.2.35. The project says Linux distributions and long-term-support vendors received patches in advance, so administrators using vendor packages should check for the corresponding updates. PHP itself no longer supports 8.1 and older, although some vendors provide backported fixes; the project also published minimal source backports for PHP 7.4, 8.0 and 8.1.
Temporary configuration changes can reduce exposure to particular attack paths, but PHP says they do not make an installation safe. Amazon recommends upgrading first, reviewing web-server logs and checking for unexpected process execution or file changes. Because its first recorded attempt predates disclosure, AWS advises security teams to investigate activity from at least October 17—not just from the day the patches appeared.