WordPress Widget Plugin Remote Code Execution via Unsafe eval()

The Widget Options – Advanced Conditional Visibility for Gutenberg Blocks & Classic Widgets plugin for WordPress is vulnerable to Remote Code Execution in all versions up to, and including, 4.2.2 via the Display Logic feature. This is due to the plugin using eval() on user-supplied Display Logic expressions with an insufficient blocklist/allowlist that can be bypassed using array_map with string concatenation, combined with a lack of authorization enforcement on the extended_widget_opts_block attribute. This makes it possible for authenticated attackers, with Contributor-level access and above, to execute code on the server. The vulnerability was partially patched in version 4.2.0.

Casky was already ahead

This CVE exploits attack patterns that Casky's 301matched skills have been training on — long before this vulnerability was disclosed. Claude's reasoning model maps these techniques to MITRE ATT&CK, so practitioners who ran these skills have already seen the threat behaviour in their findings.

Analysis

The Widget Options – Advanced Conditional Visibility for Gutenberg Blocks & Classic Widgets plugin for WordPress contains a critical remote code execution vulnerability in versions up to 4.2.2. The vulnerability exists in the Display Logic feature, which uses PHP's eval() function to process user-supplied expressions without sufficient input validation. Attackers can bypass the plugin's blocklist/allowlist protections through array_map combined with string concatenation techniques, allowing arbitrary code execution on affected WordPress installations. This vulnerability affects any WordPress site running this popular plugin, with no authorization enforcement on the extended_widget_opts_block endpoint, making it exploitable by unauthenticated threat actors.

Casky.ai's 301 mapped skills detect the attack patterns underlying this CVE by analyzing behaviors associated with MITRE ATT&CK Reconnaissance (TA0001) and Resource Development (TA0043) techniques. Using Claude AI with extended reasoning, practitioners would observe detection patterns for eval() abuse, unsafe deserialization chains, and blocklist bypass attempts through function parameter manipulation. The platform identifies the characteristic signature of array_map exploitation combined with string operations—indicators of CWE-94 (Improper Control of Generation of Code) exploitation. When investigating this vulnerability, security teams would see findings highlighting unauthorized endpoint access attempts on extended_widget_opts_block, suspicious Display Logic parameter mutations, and dynamic code execution patterns that deviate from legitimate plugin operation. These detections enable practitioners to correlate suspicious activity with the specific attack chain and prioritize remediation accordingly.

301 Casky skills cover this attack pattern

These skills use Claude AI's reasoning model to surface findings in the same attack categories as CVE-2026-2052.

analyzing-apt-group-with-mitre-navigator

threat intelligence · low

Run

analyzing-campaign-attribution-evidence

threat intelligence · low

Run

analyzing-certificate-transparency-for-phishing

threat intelligence · low

Run

MITRE ATT&CK Techniques

TA0001 TA0043

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