Craft is a content management system (CMS). Prior to 5.9.0-beta.1 and 4.17.0-beta.1, Craft CMS implements a blocklist to prevent potentially dangerous PHP functions from being called via Twig non-Closure arrow functions. In order to be able to successfully execute this attack, you need to either have allowAdminChanges enabled on production, or a compromised admin account, or an account with access to the System Messages utility.
Several PHP functions are not included in the blocklist, which could allow malicious actors with the required permissions to execute various types of payloads, including RCEs, arbitrary file reads, SSRFs, and SSTIs. This vulnerability is fixed in 5.9.0-beta.1 and 4.17.0-beta.1.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
High
Admin privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 8
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:*:*:*:*:*:*:*:*
|
> 4.0.0
|
4.17.0
|
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:*:*:*:*:*:*:*:*
|
> 5.0.0
|
5.9.0
|
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:4.0.0:-:*:*:*:*:*:*
|
— | — |
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:4.0.0:rc1:*:*:*:*:*:*
|
— | — |
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:4.0.0:rc2:*:*:*:*:*:*
|
— | — |
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:4.0.0:rc3:*:*:*:*:*:*
|
— | — |
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:5.0.0:-:*:*:*:*:*:*
|
— | — |
|
Craftcms Craft_Cms
cpe:2.3:a:craftcms:craft_cms:5.0.0:rc1:*:*:*:*:*:*
|
— | — |