October CMS safe mode bypass using Twig sandbox escape
Critical severity
GitHub Reviewed
Published
Nov 29, 2023
in
octobercms/october
•
Updated Dec 4, 2023
Description
Published to the GitHub Advisory Database
Nov 29, 2023
Reviewed
Nov 29, 2023
Published by the National Vulnerability Database
Dec 1, 2023
Last updated
Dec 4, 2023
Impact
An authenticated backend user with the
editor.cms_pages
,editor.cms_layouts
, oreditor.cms_partials
permissions who would normally not be permitted to provide PHP code to be executed by the CMS due tocms.safe_mode
being enabled can write specific Twig code to escape the Twig sandbox and execute arbitrary PHP.This is not a problem for anyone who trusts their users with those permissions to usually write and manage PHP within the CMS by not having
cms.safe_mode
enabled. Still, it would be a problem for anyone relying oncms.safe_mode
to ensure that users with those permissions in production do not have access to write and execute arbitrary PHP.Patches
This issue has been patched in v3.4.15.
Workarounds
As a workaround, remove the specified permissions from untrusted users.
References
Credits to:
For more information
If you have any questions or comments about this advisory:
References