The short version:

On 21 October 2026 PHP released urgent fixes for two critical flaws, nicknamed PHP2Shell, that let an attacker run their own code on a web server without logging in. The flaws were found with the help of AI. If your website runs on WordPress, Joomla, Drupal or any other PHP software, ask your developer or hosting company today whether PHP has been updated to 8.5.12, 8.4.27, 8.3.36 or 8.2.35.

What happened

PHP is the programming language behind WordPress and a very large share of the web. News reports put it at up to 70% of all websites.

In August 2026, researchers at Wiz used AI models to dig through PHP's own engine and found two serious memory bugs:

  • CVE-2026-109618: remote code execution through out-of-memory corruption;
  • CVE-2026-109619: remote code execution through stale global state.

Both are rated 9.2 out of 10 for severity. The worst part: an attacker does not need a password, and the attack works before your website's own code even runs. So a perfectly built website is still exposed if the PHP underneath it is old.

The PHP project was told on 24 August and published fixed versions on 21 October 2026. Wiz showed working attacks against WordPress, Drupal and Joomla.

Why everyone is talking about AI

This is one of the first times AI tools found a bug this serious in software this widely used. The researchers credit AI models, and partners at OpenAI and Calif, for the discovery.

That cuts both ways:

  • The good side: defenders can now find old, hidden bugs much faster.
  • The bad side: attackers have the same tools. Cloudflare reported tens of thousands of attack attempts within 45 minutes of the news going public.

Some websites chose to go offline for a few hours rather than stay exposed. The US NSA advised operators who couldn't patch straight away to take their sites offline temporarily. Some news outlets have started calling it AI's "Black October".

Is it only PHP?

PHP2Shell itself is a PHP problem. But AI is changing attacks on other languages too:

  • JavaScript (npm) and Python (PyPI): in May 2026 a campaign called "mini-shai-hulud" slipped malicious updates into more than 170 npm packages and 2 PyPI packages, including ones from well-known projects such as TanStack and Mistral AI.
  • "Slopsquatting": AI coding assistants sometimes suggest software packages that don't exist. Attackers register those made-up names and fill them with malware, waiting for someone to install them.

The lesson for every business is the same: old software is now found and attacked much faster than before. "We'll update next month" is no longer safe.

Five-minute checklist for your business website

If your website is on WordPress or another PHP system
ASKMessage your developer or hosting company: "Is our PHP updated for PHP2Shell (8.5.12 / 8.4.27 / 8.3.36 / 8.2.35)?"
OLD VERSION?PHP 8.1 or older gets no official fixes. Plan an upgrade now, not later.
TURN ON PROTECTIONIf your site is behind Cloudflare, its protection for this attack is already on. Keep it on.
UPDATE PLUGINSUpdate WordPress, the theme and every plugin. Delete plugins you don't use.
BACK UPMake sure a recent backup exists somewhere other than the same server.

Signs worth reporting to your developer: the site suddenly showing errors, strange new admin users, pages you didn't create, or your hosting company warning about unusual traffic.

What about KhataIN?

KhataIN does not run on PHP, so PHP2Shell does not affect KhataIN accounts, invoices, POS or the websites made with KhataIN Websites. We keep our software dependencies pinned, reviewed and updated, and we watch for supply-chain attacks like the ones above.

If you want a simple business website without managing servers, plugins or PHP updates yourself, a KhataIN website is hosted and kept up to date for you. See KhataIN's features or talk to us.

Frequently asked questions

What is PHP2Shell?

PHP2Shell is the nickname for two critical flaws in PHP (CVE-2026-109618 and CVE-2026-109619), fixed on 21 October 2026. They let an attacker run their own code on a web server that uses an unpatched PHP version, without logging in.

Is my WordPress website affected?

WordPress runs on PHP, so it is affected if the server's PHP version is older than the fixed versions: 8.5.12, 8.4.27, 8.3.36 or 8.2.35. Updating WordPress alone is not enough; PHP itself must be updated by your host or developer.

My hosting company manages the server. Do I need to do anything?

Yes: ask them to confirm in writing that PHP has been updated. Shared hosting providers usually patch quickly, but older plans and self-managed VPS servers are often missed.

Did AI really find this bug?

Yes. Wiz Research says AI models helped find the flaws, with OpenAI and Calif credited in the discovery. Attackers are using similar tools, which is why patching quickly matters more than ever.

Are KhataIN websites affected?

No. KhataIN and KhataIN Websites are not built on PHP, so these flaws don't apply to them.

Sources

  • PHP project, security releases (21 October 2026): https://www.php.net/
  • Wiz Research, "PHP2Shell: AI uncovers critical RCE vulnerabilities affecting 70% of the Internet": https://www.wiz.io/blog/php2shell-php-rce
  • Fortune, "AI tools discovered the PHP vulnerability…" (21 October 2026): https://fortune.com/2026/10/21/ai-tools-discovered-the-php-vulnerability-that-could-take-down-70-of-the-internet-now-the-race-is-on-to-patch-it-before-ai-powered-hackers-attack/
  • TidBITS, "PHP2Shell vulnerabilities put 70% of websites at risk": https://tidbits.com/2026/10/21/php2shell-vulnerabilities-put-70-of-websites-at-risk/
  • SafeDep, mass npm supply-chain attack (TanStack, Mistral AI): https://safedep.io/mass-npm-supply-chain-attack-tanstack-mistral/
  • Andrew Nesbitt, "Package security problems for AI agents": https://nesbitt.io/2026/04/08/package-security-problems-for-ai-agents.html