PT-2026-31821 · Joomla · Smart Slider 3 Pro

Published 2026-04-09 · Updated 2026-04-13 · CVE-2026-34424

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Smart Slider 3 Pro version 3.5.1.35

Description Smart Slider 3 Pro version 3.5.1.35 for WordPress and Joomla contains a multi-stage remote access toolkit injected through a compromised update system. This allows unauthenticated attackers to execute arbitrary code and commands. Attackers can trigger pre-authentication remote shell execution via HTTP headers, establish authenticated backdoors accepting arbitrary PHP code or OS commands, create hidden administrator accounts, exfiltrate credentials and access keys, and maintain persistence through multiple injection points including must-use plugins and core file modifications.

Recommendations Remove Smart Slider 3 Pro version 3.5.1.35 immediately.

Fix

RCE

Weakness Enumeration

CWE-506

Related Identifiers

CVE-2026-34424

Affected Products

Smart Slider 3 Pro

References · 12

• https://nvd.nist.gov/vuln/detail/CVE-2026-34424 · Security Note
• https://twitter.com/CVEnew/status/2042387938261287329 · Twitter Post
• https://mysites.guru/blog/smart-slider-3-pro-supply-chain-compromise · Note
• https://twitter.com/CveFindCom/status/2042387814667391487 · Twitter Post
• https://patchstack.com/database/wordpress/plugin/nextend-smart-slider3-pro/vulnerability/wordpress-smart-slider-3-plugin-3-5-1-35-backdoor-vulnerability · Note
• https://twitter.com/giuseppe_1337/status/2042383487471137079 · Twitter Post
• https://patchstack.com/articles/critical-supply-chain-compromise-in-smart-slider-3-pro-full-malware-analysis · Note
• https://smartslider.helpscoutdocs.com/article/2144-wordpress-security-advisory-smart-slider-3-pro-3-5-1-35-compromise · Patch, Vendor Advisory
• https://twitter.com/0dayPublishing/status/2042379414667763802 · Twitter Post
• https://twitter.com/OrizonCyber/status/2042467629122641957 · Twitter Post
• https://smartslider.helpscoutdocs.com/article/2143-joomla-security-advisory-smart-slider-3-pro-3-5-1-35-compromise · Patch, Vendor Advisory
• https://twitter.com/ctiwatchcloud/status/2043721059518575026 · Twitter Post