October CMS safe mode bypass using Twig sandbox escape
Published 29 Nov 2023 · Updated 4 Dec 2023
Affected package
- Affected
- >=3.0.0 <3.4.15
- Fixed in
- 3.4.15
composer require october/system:^3.4.15Details
Impact
An authenticated backend user with the editor.cms_pages, editor.cms_layouts, or editor.cms_partials permissions who would normally not be permitted to provide PHP code to be executed by the CMS due to cms.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 on cms.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:
- Email us at [hello@octobercms.com](mailto:hello@octobercms.com)
Is GHSA-p8q3-h652-65vx in any of your client repos?
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References
Advisory data from OSV.dev (opens OSV.dev in a new tab), refreshed daily.