CVE-2021-21264 (GCVE-0-2021-21264)

Vulnerability from cvelistv5 – Published: 2021-05-03 16:00 – Updated: 2024-08-03 18:09
VLAI
Title
Bypass of fix for CVE-2020-26231, Twig sandbox escape
Summary
October is a free, open-source, self-hosted CMS platform based on the Laravel PHP Framework. A bypass of CVE-2020-26231 (fixed in 1.0.470/471 and 1.1.1) was discovered that has the same impact as CVE-2020-26231 & CVE-2020-15247. An authenticated backend user with the `cms.manage_pages`, `cms.manage_layouts`, or `cms.manage_partials` permissions who would **normally** not be permitted to provide PHP code to be executed by the CMS due to `cms.enableSafeMode` being enabled is able to write specific Twig code to escape the Twig sandbox and execute arbitrary PHP. This is not a problem for anyone that trusts their users with those permissions to normally write & manage PHP within the CMS by not having `cms.enableSafeMode` enabled, but would be a problem for anyone relying on `cms.enableSafeMode` to ensure that users with those permissions in production do not have access to write & execute arbitrary PHP. Issue has been patched in Build 472 (v1.0.472) and v1.1.2. As a workaround, apply https://github.com/octobercms/october/commit/f63519ff1e8d375df30deba63156a2fc97aa9ee7 to your installation manually if unable to upgrade to Build 472 or v1.1.2.
Severity
5.2 (Medium)
CVSS:3.1/AV:L/AC:L/PR:H/UI:R/S:C/C:L/I:L/A:L
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7861 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
octobercms october Affected: 1.0.471
Affected: 1.1.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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