SB2021050301 - Twig sandbox bypass in October CMS



SB2021050301 - Twig sandbox bypass in October CMS

Published: May 3, 2021

Security Bulletin ID SB2021050301
CSH Severity
Medium
Patch available
YES
Number of vulnerabilities 1
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

Medium 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 1 vulnerability.


1) Code Injection (CVE-ID: CVE-2021-21264)

CWE-ID: CWE-94 - Improper Control of Generation of Code ('Code Injection')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Green


The vulnerability allows a remote user to execute arbitrary PHP code on the target system.

The vulnerability exists due to incomplete patch implementation for previously patched vulnerabilities #VU48707 and #VU48710. A remote authenticated user with the cms.manage_pages, cms.manage_layouts, or cms.manage_partials permissions can  write specific Twig code to escape the Twig sandbox and execute arbitrary PHP.


Remediation

Install update from vendor's website.