Drupal Core: Gadget Chain Can Turn Another Unserialize Bug Into Code Execution
Published as "Drupal core allows Object Injection"
- CVE
- CVE-2026-6366
- GHSA
- GHSA-xmjc-63pr-2mpg
- Packagist
- PKSA-j351-xv4b-pryh
- Reported
- May 20, 2026
Gives attackers a path to code execution or SQL injection on Drupal sites that already have another flaw passing untrusted data to unserialize().
Affected and fixed versions
In drupal/core.
Find the row for the version you run, and update to the release next to it.
| If you run | Update to | Support |
|---|---|---|
| 11.3.0 – 11.3.6 | 11.3.7 | Supported |
| 10.6.0 – 10.6.6 | 10.6.7 | Supported |
Show 2 older branches, no longer supported
| 11.0.0 – 11.2.10 | 11.2.11 |
| 8.0.0 – 10.5.8 | 10.5.9 |
Upgrade
Run the line for the branch you are on.
composer require drupal/core:^11.3.7 composer require drupal/core:^10.6.7
Check your app with an agent
Paste this into a coding agent that can read your project, such as Claude Code, Codex or Amp. It checks your composer.lock against the versions above and tells you what to update, without changing anything.
Check whether the PHP project you have access to is affected by this security advisory, and tell me what to update. Do a read-only check: don't edit files, don't run composer update or composer require, and don't try to reproduce the flaw. Advisory: Drupal Core: Gadget Chain Can Turn Another Unserialize Bug Into Code Execution (CVE-2026-6366, GHSA-xmjc-63pr-2mpg) Details: https://phpnews.net/security/drupal/ghsa-xmjc-63pr-2mpg Affected versions, as Composer constraints: - drupal/core: >=11.3.0,<11.3.7|>=11.0.0,<11.2.11|>=10.6.0,<10.6.7|>=8.0.0,<10.5.9 Fixed releases on branches that still get security fixes: - 11.3.0 – 11.3.6: update to 11.3.7 - 10.6.0 – 10.6.6: update to 10.6.7 1. Find every composer.lock in the project outside vendor/ (a monorepo can have one per app) and read the installed version of each package above. Packages installed as dependencies of other packages count too. 2. Compare each installed version with its constraint: "|" separates alternative ranges, and "," means both bounds apply. 3. For each affected install, read the project's advisory at https://github.com/advisories/GHSA-xmjc-63pr-2mpg and check whether the project meets the conditions it describes. Say which conditions you could check and which you couldn't. 4. Report a table: lock file | package | installed version | affected (yes, no or unknown) | conditions met (yes, no or unknown) | update to | evidence. For each affected package, give the command that would fix it, without running it: composer update <package> --with-dependencies when it is only installed as a dependency of another package, or composer require with the fixed version when composer.json requires it directly. If the installed version is on a branch with no fixed release listed, say it needs a move to a newer branch.