CVE-2025-52828: Red Art Deserialization Vulnerability

CVE-2025-52828 Overview

CVE-2025-52828 is a PHP Object Injection vulnerability in the designthemes Red Art WordPress theme. The flaw stems from deserialization of untrusted data [CWE-502] and affects all versions of Red Art up to and including 3.8. An authenticated attacker with low privileges can pass crafted serialized payloads to vulnerable code paths, triggering instantiation of arbitrary PHP objects. When combined with usable magic method gadgets present in WordPress core, plugins, or themes, exploitation can lead to remote code execution, arbitrary file operations, or full site compromise.

Critical Impact
Authenticated attackers can inject malicious PHP objects to execute arbitrary code and compromise the confidentiality, integrity, and availability of the affected WordPress site.

Affected Products

designthemes Red Art WordPress theme — all versions through 3.8
WordPress installations using the Red Art theme as the active or fallback theme
Sites bundling vulnerable Red Art assets alongside other designthemes products

Discovery Timeline

2025-07-04 - CVE-2025-52828 published to NVD
2026-04-23 - Last updated in NVD database

Technical Details for CVE-2025-52828

Vulnerability Analysis

The vulnerability is an Insecure Deserialization issue classified under [CWE-502]. The Red Art theme passes attacker-controllable input to a PHP deserialization routine such as unserialize() without validating its origin or contents. When PHP reconstructs an object from the serialized payload, it invokes magic methods including __wakeup(), __destruct(), and __toString() on classes loaded in the runtime. Attackers chain these magic methods into property-oriented programming gadgets to reach dangerous sinks like file writes, SQL queries, or command execution.

Exploitation requires network access and low-privilege authenticated access, with no user interaction. The scope remains unchanged, but confidentiality, integrity, and availability impacts are all high. The EPSS score is 0.336% at the 56th percentile, indicating measurable but not widespread exploitation prediction.

Root Cause

The root cause is the theme's reliance on unserialize() against data sourced from HTTP requests, cookies, transients, or stored options without integrity validation. WordPress themes frequently use serialized blobs to persist complex settings, and Red Art exposes one or more such code paths to authenticated users. Because PHP's deserializer eagerly instantiates classes, any gadget chain present in loaded plugins becomes reachable.

Attack Vector

An authenticated attacker, such as a subscriber or contributor depending on the affected endpoint, submits a crafted serialized payload to a Red Art theme endpoint, AJAX handler, or option-saving routine. The theme deserializes the payload, instantiating attacker-chosen objects. Triggered magic methods execute the gadget chain, which can write PHP files into the webroot, modify database records, or invoke system commands through gadgets present in the WordPress environment.

Technical details are documented in the Patchstack advisory for Red Art PHP Object Injection.

Detection Methods for CVE-2025-52828

Indicators of Compromise

Unexpected PHP files appearing in wp-content/themes/redart/ or wp-content/uploads/ after authenticated requests
HTTP POST bodies, cookies, or query parameters containing serialized PHP patterns such as O: (object), a: (array), or s: (string) markers
New or modified WordPress administrator accounts and altered wp_options entries created shortly after Red Art endpoint access
Outbound connections from the web server to attacker-controlled hosts following theme-related requests

Detection Strategies

Inspect web server access logs for requests to Red Art theme endpoints carrying serialized payloads (O:\d+: patterns) from authenticated sessions
Monitor PHP error logs for __wakeup, __destruct, or class-not-found errors that often accompany failed deserialization gadget attempts
Apply file integrity monitoring to the active theme directory and wp-content/uploads/ to catch attacker-dropped PHP backdoors
Correlate authenticated low-privilege user activity with subsequent privilege changes or option modifications in the WordPress database

Monitoring Recommendations

Enable WordPress audit logging to capture option updates, user role changes, and theme settings modifications
Forward web server, PHP-FPM, and WordPress logs to a centralized SIEM with retention for at least 90 days
Alert on HTTP requests containing serialized object markers from non-administrator user sessions
Track outbound HTTP and DNS traffic from the WordPress host to identify post-exploitation command and control activity

How to Mitigate CVE-2025-52828

Immediate Actions Required

Update the designthemes Red Art theme to a version newer than 3.8 once the vendor releases a patched build
Restrict authenticated registration on affected sites and audit existing low-privilege accounts for suspicious activity
Review the active theme and wp-content/uploads/ directories for unauthorized PHP files and remove any backdoors
Rotate WordPress administrator credentials, secret keys in wp-config.php, and any API tokens stored in theme options

Patch Information

Refer to the Patchstack advisory for the latest vendor remediation status. The advisory tracks all versions through 3.8 as vulnerable. Site operators should obtain the fixed release directly from designthemes when available and verify the installed version through the WordPress admin dashboard.

Workarounds

Deploy a Web Application Firewall rule that blocks HTTP request parameters matching PHP serialization patterns such as O:[0-9]+:"
Switch to an alternative theme until a patched Red Art release is installed and verified
Remove or rename unused Red Art endpoints and AJAX handlers to reduce the attack surface
Apply least-privilege principles by disabling user self-registration and limiting roles that can reach theme settings

bash

# Example WAF rule (ModSecurity) to block PHP object injection patterns
SecRule ARGS|REQUEST_COOKIES|REQUEST_HEADERS "@rx O:[0-9]+:\"[a-zA-Z_\\\\]+\":[0-9]+:" \
  "id:1052828,phase:2,deny,status:403,log,\
  msg:'CVE-2025-52828 Red Art PHP Object Injection attempt'"