On October 21, 2026, two critical PHP vulnerabilities were disclosed. This is particularly troublesome for operators of older Magento stores still running PHP 5.6, PHP 7.4 or another unsupported PHP version. A simple PHP upgrade is often impossible without updating Magento and numerous extensions at the same time.
The vulnerabilities CVE-2026-109618 and CVE-2026-109619 may, under certain conditions, allow attackers to execute code on the server, potentially without being logged in first. Both were rated 9.2 in severity.
Why older Magento stores are especially affected
Many Magento 1 installations still rely on PHP 5.x or PHP 7.x. Older Magento 2 versions may also depend on specific PHP versions.
Switching to PHP 8.3 or 8.4 can therefore break a store. Outdated libraries, custom extensions and Magento core modifications can turn an upgrade into a substantial project.
The problem is: PHP 5.x and PHP 7.x no longer receive regular security updates. A store that ran perfectly yesterday may therefore face significant additional risk today.
Older PHP 8 versions may also be affected. A version number beginning with 8 does not, by itself, mean a system is secure.
What can store owners do now?
The good news is that reducing the immediate risk does not always require a complete Magento upgrade straight away.
Depending on your server configuration, consider the following:
- Secure your web server: Block malicious requests as early as possible through Apache, nginx or an upstream firewall.
- Harden PHP configuration: Disable unnecessary PHP functions and restrict dangerous request processing at the server level.
- Protect the admin area: Add extra protection for Magento admin and reduce unnecessary public access.
- Check your hosting environment: Ask whether your provider supplies security fixes for the older PHP release you use.
- Review Magento extensions: Remove unused functionality and restrict potentially vulnerable interfaces.
Important: These measures do not replace a security patch for PHP itself. They can limit some attack vectors but cannot provide complete protection. In some cases, taking a vulnerable installation temporarily offline may be necessary.
Why not simply upgrade PHP?
With a current Magento 2 store, moving to a supported PHP version may be relatively straightforward if the installed extensions are compatible.
Magento 1 and older Magento 2 installations are different. Their dependencies must be reviewed first. Some extensions can be adapted; elsewhere, a more substantial modernization may be required.
A blanket PHP upgrade is therefore not a good idea. The store still needs to work properly after the security changes.
I can help secure your Magento store
Running Magento 1 or Magento 2 on PHP 5.6, 7.4 or another outdated PHP version and unsure how to respond to the latest security vulnerabilities?
Please contact me.
I can assess your Magento installation, PHP environment and options for short-term mitigation. The first priority is understanding the real exposure and implementing sensible measures without unnecessarily disrupting a working store.
If a lasting upgrade is needed, we can plan the appropriate route, from adapting individual extensions to a full Magento upgrade.
Further information
Official details about the vulnerabilities, affected PHP versions and available patches can be found directly from PHP development team.