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Concrete 5 CMS

v9.5.2 Security

This release includes 2 security fixes for security teams reviewing exposed deployments.

Published 1d Productivity & Wikis
✓ No known CVEs patched
Read the diff → Tool health → What is this tool? →
This release patches 2 known CVEs

Topics

cms concrete5 concretecms content-management-system php

Affected surfaces

deps rce_ssrf

ReleasePort's take

Moderate signal
editorial:auto 1d

Version 9.5.2 updates third‑party libraries and hardens unserialize() calls to block PHP Object Injection.

Why it matters: Security fixes close vulnerabilities in twig/twig, symfony/yaml, and enforce allowed_classes on unserialize(), mitigating injection risks across all deployments.

Summary

AI summary

Updates Bug Fixes, Security Fixes, and Behavioral Improvements across a mixed release.

Changes in this release

Security Critical

Updated third party composer libraries to close out new security vulnerabilities (twig/twig, symfony/yaml).

Updated third party composer libraries to close out new security vulnerabilities (twig/twig, symfony/yaml).

Source: llm_adapter@2026-06-02

Confidence: high

Security Critical

Added allowed_classes parameter to unserialize() calls in Permission, Cache, Search to prevent PHP Object Injection.

Added allowed_classes parameter to unserialize() calls in Permission, Cache, Search to prevent PHP Object Injection.

Source: llm_adapter@2026-06-02

Confidence: high

Security Critical

Added allowed_classes parameter to unserialize() calls in Workflow, Form blocks, and File/Set to prevent PHP Object Injection.

Added allowed_classes parameter to unserialize() calls in Workflow, Form blocks, and File/Set to prevent PHP Object Injection.

Source: llm_adapter@2026-06-02

Confidence: high

Feature Low

Added `on_package_test_for_uninstall`, `on_before_package_uninstall`, and `on_after_package_uninstall` events for developers.

Added `on_package_test_for_uninstall`, `on_before_package_uninstall`, and `on_after_package_uninstall` events for developers.

Source: llm_adapter@2026-06-02

Confidence: high

Bugfix Medium

Restored old behavior: custom template missing renders default view instead of nothing.

Restored old behavior: custom template missing renders default view instead of nothing.

Source: llm_adapter@2026-06-02

Confidence: high

Bugfix Medium

Fixed misplaced closing anchor tag in calendar event date output.

Fixed misplaced closing anchor tag in calendar event date output.

Source: llm_adapter@2026-06-02

Confidence: high

Full changelog

Behavioral Improvements

  • Page attributes are now grouped by set in the Composer Add Form Control dialog.

Bug Fixes

  • Advanced board templates that used the $summaryObject variable within them should now work again.
  • Restored old behavior where if a block used a custom template, but that custom template actually didn’t exist in the filesystem, the block would not render anything. Now it renders the default view (as it used to.)
  • Fixed: In the date output of a calendar event there was a closing anchor tag which appears to be out of place (thanks danklassen)

Developer Updates

  • Added on_package_test_for_uninstall, on_before_package_uninstall and on_after_package_uninstall events.

Security Fixes

  • Updated third party composer libraries to close out new security vulnerabilities in our upstream dependencies like twig/twig, symfony/yaml, and others.
  • add allowed_classes to unserialize() in Permission, Cache, and Search to prevent PHP Object Injection (thanks XananasX7)
  • security: add allowed_classes to unserialize() in Workflow, Form blocks, and File/Set(thanks XananasX7)

Security Fixes

  • Added allowed_classes to unserialize() in Permission, Cache, Search, Workflow, Form blocks, and File/Set to prevent PHP Object Injection
  • Updated third‑party composer libraries (twig/twig, symfony/yaml) to close new security vulnerabilities

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