CVE-2026-22346: Slider Responsive Slideshow Vulnerability

CVE-2026-22346 Overview

CVE-2026-22346 is an Insecure Deserialization vulnerability affecting the A WP Life Slider Responsive Slideshow WordPress plugin (also known as "Image slider, Gallery slideshow"). This vulnerability allows authenticated attackers to perform PHP Object Injection attacks through the deserialization of untrusted data. When exploited, this flaw can lead to arbitrary code execution, data manipulation, or complete site compromise depending on the gadget chains available within the WordPress installation.

Critical Impact

Authenticated attackers with at least subscriber-level privileges can inject malicious PHP objects, potentially leading to remote code execution, privilege escalation, or complete WordPress site takeover.

Affected Products

• Slider Responsive Slideshow – Image slider, Gallery slideshow plugin versions up to and including 1.5.4
• WordPress installations running vulnerable versions of the slider-responsive-slideshow plugin
• Sites with additional plugins or themes containing exploitable PHP gadget chains

Discovery Timeline

• 2026-02-20 - CVE CVE-2026-22346 published to NVD
• 2026-02-24 - Last updated in NVD database

Technical Details for CVE-2026-22346

Vulnerability Analysis

This vulnerability stems from CWE-502: Deserialization of Untrusted Data. The Slider Responsive Slideshow plugin fails to properly validate and sanitize serialized data before passing it to PHP's unserialize() function. When user-controlled data is deserialized without adequate safeguards, attackers can craft malicious serialized objects that execute arbitrary code or perform unauthorized actions when instantiated.

PHP Object Injection vulnerabilities are particularly dangerous in WordPress environments because the extensive plugin ecosystem often provides numerous "gadget chains" – sequences of class methods that can be chained together to achieve code execution. Even if the vulnerable plugin itself doesn't contain exploitable classes, other installed plugins or WordPress core may provide the necessary components for a successful attack.

The network-accessible nature of this vulnerability means attackers can exploit it remotely, though authentication is required. The lack of user interaction requirements makes this vulnerability easier to exploit in automated attack scenarios.

Root Cause

The root cause of CVE-2026-22346 lies in the plugin's handling of serialized data without proper validation. The slider-responsive-slideshow plugin accepts and processes serialized PHP data from user-controllable input sources. Instead of using safe data interchange formats like JSON or implementing strict allowlists for deserializable classes, the plugin directly unserializes potentially malicious payloads.

PHP's native unserialize() function automatically invokes magic methods such as __wakeup(), __destruct(), and __toString() on the reconstructed objects. Attackers exploit this behavior by crafting serialized objects that trigger dangerous operations through these magic methods, leading to arbitrary code execution or other security violations.

Attack Vector

The attack vector is network-based and requires low-privilege authentication (such as a WordPress subscriber account). An attacker would typically:

1. Identify the presence of the vulnerable Slider Responsive Slideshow plugin
2. Authenticate to the WordPress site with any valid user credentials
3. Craft a malicious serialized PHP object payload targeting available gadget chains
4. Submit the payload through the vulnerable plugin functionality
5. Upon deserialization, the malicious object triggers the gadget chain, achieving code execution

The vulnerability exploits improper input validation where serialized data is processed without verification. When the unserialize() function processes attacker-controlled input, it instantiates the embedded objects and triggers their magic methods. Common exploitation scenarios include leveraging POP (Property Oriented Programming) chains to write files to disk, execute system commands, or establish persistent backdoors.

For detailed technical information about this vulnerability, refer to the Patchstack security advisory.

Detection Methods for CVE-2026-22346

Indicators of Compromise

• Unusual serialized data patterns in HTTP POST requests to WordPress, particularly containing PHP class names
• Unexpected file modifications or new PHP files in plugin or theme directories
• WordPress user accounts exhibiting suspicious activity patterns or privilege changes
• Server logs showing unusual process execution or outbound network connections originating from the web server process

Detection Strategies

• Monitor web application logs for requests containing serialized PHP data (look for strings matching patterns like O:[0-9]+:" or a:[0-9]+:{)
• Implement web application firewall (WAF) rules to detect and block PHP object injection payloads
• Deploy file integrity monitoring on the WordPress installation to detect unauthorized modifications
• Review WordPress audit logs for suspicious plugin-related activities from low-privilege users

Monitoring Recommendations

• Enable verbose logging for the WordPress installation and monitor for deserialization-related errors
• Configure intrusion detection systems to alert on patterns consistent with PHP object injection attempts
• Regularly audit installed plugin versions against known vulnerability databases
• Monitor for unexpected process spawning or network connections from the web server

How to Mitigate CVE-2026-22346

Immediate Actions Required

• Update the Slider Responsive Slideshow plugin to a patched version if one is available from the vendor
• If no patch is available, immediately deactivate and remove the slider-responsive-slideshow plugin
• Review WordPress user accounts and remove any unnecessary subscriber or contributor accounts
• Conduct a thorough security audit of the WordPress installation for signs of compromise

Patch Information

Organizations should check for available updates through the WordPress plugin repository or the vendor's official channels. The Patchstack advisory provides the most current information regarding patch availability. Until an official patch is released, removal of the vulnerable plugin is the recommended remediation approach.

Workarounds

• Disable the Slider Responsive Slideshow plugin until a security patch is available
• Implement strict WAF rules to filter requests containing serialized PHP data
• Restrict WordPress user registration and minimize the number of authenticated accounts
• Consider deploying a virtual patching solution through a WordPress security plugin

# WordPress CLI commands to check and disable the vulnerable plugin
# Check if the vulnerable plugin is installed
wp plugin list --name=slider-responsive-slideshow --format=table

# Deactivate the plugin if found
wp plugin deactivate slider-responsive-slideshow

# Optional: Remove the plugin entirely
wp plugin delete slider-responsive-slideshow