Embedded malicious code (backdoor) in Smart Slider 3 - #VU125748

Detailed vulnerability description

The vulnerability allows a remote attacker to gain unauthorized access to the application.

The vulnerability exists due to presence of embedded malicious functionality in the application code (aka backdoor) that allows a remote attacker to gain unauthorized access to the application.

Note, an unauthorized party gained access to Nextend update infrastructure on April 7 and distributed a fully attacker-authored build through the official update channel. Only version 3.5.1.35 contained the backdoor code.

Remediation

Sources

• https://patchstack.com/articles/critical-supply-chain-compromise-in-smart-slider-3-pro-full-malware-analysis/
• https://patchstack.com/database/wordpress/plugin/nextend-smart-slider3-pro/vulnerability/wordpress-smart-slider-3-plugin-3-5-1-35-backdoor-vulnerability