CVE-2024-7434: UltraPress WordPress Theme RCE Vulnerability

CVE-2024-7434 Overview

The UltraPress theme for WordPress contains a PHP Object Injection vulnerability affecting all versions up to and including 1.2.2. The flaw stems from deserialization of untrusted input, allowing authenticated attackers with Contributor-level access or higher to inject arbitrary PHP objects. While no Property-Oriented Programming (POP) chain exists in the base theme, chained exploitation through additional plugins or themes can lead to arbitrary file deletion, sensitive data disclosure, or code execution.

Critical Impact
Authenticated Contributor-level attackers can inject PHP objects that, combined with a POP chain from another installed component, enable arbitrary file deletion, data exfiltration, or remote code execution on affected WordPress sites.

Affected Products

UltraPress theme for WordPress (all versions ≤ 1.2.2)
WordPress sites with Contributor-level or higher user accounts enabled
Deployments combining UltraPress with plugins or themes exposing POP chains

Discovery Timeline

2024-10-01 - CVE-2024-7434 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-7434

Vulnerability Analysis

The vulnerability is classified as Insecure Deserialization [CWE-502]. UltraPress passes attacker-controlled input to a PHP deserialization function without validation. When PHP unserializes attacker-supplied data, it instantiates arbitrary objects and invokes magic methods such as __wakeup() or __destruct() on them.

An authenticated attacker with Contributor privileges can craft a serialized payload and submit it through a theme code path that deserializes user input. The base UltraPress theme does not ship a usable POP chain. However, WordPress installations typically load additional plugins and themes that define classes with dangerous magic methods.

When such classes exist in the runtime, the injected object triggers method calls that can delete files, read arbitrary data, or execute code. The EPSS score is 0.629% with a percentile of 47.434, reflecting moderate real-world exploitation likelihood.

Root Cause

The root cause is the use of PHP unserialize() on input reachable by authenticated users without prior integrity validation or type restrictions. Safer alternatives such as json_decode() or unserialize() with an allowed_classes allowlist are not used.

Attack Vector

Exploitation requires network access to the WordPress site and valid credentials for an account with Contributor role or higher. The attacker submits a serialized PHP object payload through the vulnerable request handler in UltraPress. Deserialization triggers automatic invocation of magic methods on classes available in the WordPress runtime. If a gadget chain exists in any installed plugin or theme, the attacker chains it to achieve file deletion, data disclosure, or code execution.

No verified public exploit code is available for this vulnerability. Refer to the Wordfence Vulnerability Report for additional technical context.

Detection Methods for CVE-2024-7434

Indicators of Compromise

HTTP POST requests to UltraPress theme endpoints containing serialized PHP payloads beginning with tokens such as O:, a:, or s:.
Unexpected creation, modification, or deletion of files within the WordPress installation directory following Contributor-level activity.
PHP error log entries referencing unserialize(), __wakeup(), or __destruct() from theme code paths.
New or modified WordPress user accounts with elevated privileges appearing after suspicious Contributor logins.

Detection Strategies

Inspect web server logs for requests to UltraPress endpoints containing serialized object markers in POST bodies or query parameters.
Correlate Contributor-role authentication events with subsequent file system changes under wp-content/.
Deploy a Web Application Firewall (WAF) rule that flags PHP serialization patterns in request parameters targeting theme handlers.

Monitoring Recommendations

Enable WordPress audit logging for user role changes, file edits, and plugin or theme installations.
Monitor outbound network connections from the PHP-FPM or web server process for signs of post-exploitation callbacks.
Alert on PHP fatal errors and warnings referencing deserialization in application logs.

How to Mitigate CVE-2024-7434

Immediate Actions Required

Update the UltraPress theme to a version later than 1.2.2 once the vendor publishes a patched release.
Audit all WordPress user accounts and revoke unnecessary Contributor, Author, Editor, and Administrator privileges.
Review installed plugins and themes for known POP gadget chains and remove unused components.
Rotate credentials for any accounts that may have been used to submit suspicious serialized payloads.

Patch Information

At the time of the NVD entry, no fixed version is listed for the UltraPress theme. Administrators should monitor the WordPress theme repository and the Wordfence Vulnerability Report for release information and apply updates as soon as they become available.

Workarounds

Deactivate and remove the UltraPress theme until a patched version is released.
Restrict Contributor-level and above account creation and require strong authentication with multi-factor authentication.
Deploy WAF rules blocking requests containing serialized PHP object markers (O:, a:) to theme endpoints.
Harden PHP by disabling dangerous functions where feasible and running the web server under a least-privilege user account.

bash

# Example WAF rule pattern (ModSecurity) to block PHP object injection
SecRule ARGS "@rx (?i)(^|[^a-z])O:[0-9]+:\"[a-z0-9_\\\\]+\":[0-9]+:" \
    "id:1007434,phase:2,deny,status:403,log,\
    msg:'Possible PHP Object Injection payload (CVE-2024-7434)'"