Description
Blocksy Companion Pro plugin for WordPress before 2.1.47 contains an unauthenticated arbitrary file upload vulnerability that allows attackers to upload executable files by bypassing extension validation in the save_attachments function exposed through the Advanced Reviews feature. Attackers can exploit the Custom Fonts extension's flawed strpos() substring check by uploading double-extension filenames such as shell.woff2.php, causing the validation to pass on the substring match while the web server executes the file as PHP, achieving remote code execution.
CVSS breakdown
CVSS 4.0
Attack Vector
Network
Attack Complexity
Low
Attack Requirements
Present
Privileges Required
None
User Interaction
None
Confidentiality (Vulnerable System)
High
Integrity (Vulnerable System)
High
Availability (Vulnerable System)
High
Confidentiality (Subsequent System)
None
Integrity (Subsequent System)
None
Availability (Subsequent System)
None
CVSS 3.1
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Affected products
- Creative Themes / Blocksy Companion0 – 2.1.46
- Creative Themes / Blocksy Companion2.1.47 – 2.1.47
Exploits & proofs of concept
- exploit-dbBlocksy Companion 2.1.46 - RCEby banyamer
References
- MISChttps://www.wordfence.com/threat-intel/vulnerabilities/wordpress-plugins/blocksy-companion/blocksy-companion-2146-unauthenticated-arbitrary-file-upload-via-blc-review-images-parameter
- MISChttps://patchstack.com/database/wordpress/plugin/blocksy-companion/vulnerability/wordpress-blocksy-companion-plugin-2-1-46-unauthenticated-arbitrary-file-upload-vulnerability
- MISChttps://wordpress.org/plugins/blocksy-companion/
- VENDOR_ADVISORYhttps://www.vulncheck.com/advisories/blocksy-companion-pro-unauthenticated-file-upload-via-save-attachments
Updated 14m ago · 8 sources