Content Synchronizer security updates, in plain English

Content Synchronizer

2,001 sites report using it · on drupal.org · 1 security update explained here

This module allows administrators to move content between different websites using uploaded archive files.

Below is every security update for Content Synchronizer that this site has covered, newest first. Each one says who could exploit it, whether it applies to your site, how urgent it is, and what to tell your developer. If your site uses this module and you are not sure which version, that is the first question to ask whoever looks after it.

Content Synchronizer

Critical · 2,001 sites report using it · 2 security fixes · Week of 4 November 2026

2 security fixes in one update. Content Synchronizer fixed 2 separate security bugs at once: 1 remote code execution, 1 cross site scripting. One update covers all of them. The most serious, SA-CONTRIB-2026-293, is explained here and the full list is at the end of the card.

The module unsafely processes the contents of uploaded archive files. An administrator account could upload a malicious file to run harmful code on the server. They could view any information or alter any data including the code itself.

Who could do thisOnly someone with an administrator login.
Does it apply to youAny site using this module.
Has it been used in attacksNo sign of it.
How urgentDrupal rates this critical. Cyber Essentials expects a fix within 14 days. Do it this week.

Tell your developerUpdate Content Synchronizer to 4.1.1.

For developers: what the fix changed

This release carries 2 security fixes. The summary below is for SA-CONTRIB-2026-293, the most serious of them.

The fix prevents PHP Object Injection by unsetting the `block_serialized` key from the plugin configuration in `LayoutBuilderProcessor.php` during import. This ensures untrusted data is not passed to core's `unserialize()` function.

Also in this release Added GitLab CI configuration, fixed download archive URL handling, added empty results text in LaunchExportForm, and merged properties in EntityProcessorBase.

4.1.0 to 4.1.1 8 commits, 9 files including 3 tests.

.gitlab-ci.yml +39 −0
content_synchronizer.info.yml +1 −1
libraries/javascript/download_archive.js +2 −2
src/Form/LaunchExportForm.php +6 −0
src/Plugin/content_synchronizer/type_processor/LayoutBuilderProcessor.php +7 −0 fix
src/Processors/Entity/EntityProcessorBase.php +1 −8

Full diff, 4.1.0 to 4.1.1

The comparison is against the release immediately before the fix. If your site is on an older release, more will have changed.

All 2 security bugs this update fixes, worst first. Each link is the drupal.org notice for that one.

Critical · Remote code execution · SA-CONTRIB-2026-293
Moderately critical · Cross site scripting · SA-CONTRIB-2026-294

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Content Synchronizer

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