CVE-2026-25031: Tasty Daily Object Injection Vulnerability

CVE-2026-25031 Overview

CVE-2026-25031 is a critical Insecure Deserialization vulnerability affecting the Tasty Daily WordPress theme (tastydaily) developed by park_of_ideas. The vulnerability allows unauthenticated attackers to inject malicious PHP objects through untrusted data deserialization, potentially leading to remote code execution, data manipulation, or complete site compromise.

Critical Impact

Unauthenticated attackers can exploit PHP Object Injection to execute arbitrary code, access sensitive data, or take full control of affected WordPress installations.

Affected Products

• Tasty Daily WordPress Theme versions prior to 1.27
• WordPress installations using the tastydaily theme

Discovery Timeline

• 2026-03-25 - CVE CVE-2026-25031 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-25031

Vulnerability Analysis

This vulnerability stems from improper handling of serialized data within the Tasty Daily WordPress theme. PHP Object Injection occurs when user-controllable input is passed to the unserialize() function without proper validation. When exploited, an attacker can instantiate arbitrary PHP objects with attacker-controlled properties, potentially triggering dangerous "magic methods" such as __wakeup(), __destruct(), or __toString().

The attack is particularly dangerous in WordPress environments because the presence of "gadget chains" within WordPress core, installed plugins, or the theme itself can be leveraged to escalate the object injection into more severe attacks including remote code execution, file deletion, or database manipulation.

Root Cause

The root cause is a CWE-502 (Deserialization of Untrusted Data) vulnerability where the Tasty Daily theme processes serialized data from untrusted sources without adequate sanitization or validation. The theme fails to implement secure deserialization practices, allowing attackers to craft malicious serialized payloads that execute unintended code paths when deserialized.

Attack Vector

The vulnerability is exploitable over the network without requiring authentication or user interaction. An attacker can craft a malicious HTTP request containing a specially crafted serialized PHP object. When the vulnerable code path deserializes this input, the attacker's payload is instantiated as a PHP object, potentially triggering destructive operations through available gadget chains in the WordPress ecosystem.

The attack typically follows this pattern:

1. The attacker identifies a user-controllable input that undergoes deserialization
2. The attacker analyzes available classes with exploitable magic methods
3. A Property Oriented Programming (POP) chain is constructed using available gadgets
4. The malicious serialized payload is sent to the vulnerable endpoint
5. Upon deserialization, the object chain executes the attacker's intended operations

Detection Methods for CVE-2026-25031

Indicators of Compromise

• Unusual serialized data patterns in HTTP request parameters or cookies, particularly containing PHP class names
• Unexpected file modifications or new files created in the WordPress installation directory
• Anomalous database queries or unauthorized administrative actions
• Web server logs showing requests with long encoded payloads to theme-related endpoints

Detection Strategies

• Implement Web Application Firewall (WAF) rules to detect and block serialized PHP object patterns in requests
• Deploy file integrity monitoring to detect unauthorized changes to WordPress core, theme, and plugin files
• Enable WordPress security audit logging to track suspicious administrative activities
• Use SentinelOne Singularity XDR to monitor for process execution anomalies originating from the web server

Monitoring Recommendations

• Monitor web server error logs for PHP deserialization-related errors or warnings
• Implement real-time alerting for any new file creation or modification within the WordPress wp-content/themes/tastydaily/ directory
• Track outbound network connections from the web server that may indicate successful exploitation and command-and-control communication

How to Mitigate CVE-2026-25031

Immediate Actions Required

• Update the Tasty Daily theme to version 1.27 or later immediately
• If updating is not immediately possible, consider temporarily disabling or removing the Tasty Daily theme
• Review web server and WordPress logs for signs of exploitation attempts
• Conduct a security audit of the WordPress installation for any indicators of compromise

Patch Information

The vulnerability affects Tasty Daily theme versions prior to 1.27. Site administrators should update to version 1.27 or later through the WordPress admin dashboard or by manually downloading the patched version from the theme vendor. For detailed vulnerability information, refer to the Patchstack Vulnerability Report.

Workarounds

• Implement a Web Application Firewall with rules to filter serialized PHP object patterns in incoming requests
• Restrict access to the WordPress admin area by IP address where feasible
• Enable WordPress Multisite or additional security plugins that provide input sanitization layers
• Consider switching to an alternative theme until the patch can be applied if immediate updating is not possible