CVE-2026-59533 in Relevanssi Light Plugin
Summary
by MITRE • 07/27/2026
Unauthenticated SQL Injection in Relevanssi Light <= 1.2.2 versions.
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Analysis
by VulDB Data Team • 07/27/2026
This vulnerability represents a critical security flaw in the Relevanssi Light plugin for WordPress, affecting versions 1.2.2 and earlier. The issue stems from insufficient input validation and sanitization within the plugin's search functionality, allowing malicious actors to inject arbitrary SQL commands into database queries. The vulnerability exists because the plugin fails to properly escape user-supplied parameters before incorporating them into SQL statements, creating an environment where attackers can manipulate database operations through crafted search inputs.
The technical implementation of this flaw involves the plugin's handling of search parameters within its lightweight indexing and retrieval mechanisms. When users perform searches through the Relevanssi Light interface, the plugin constructs SQL queries using raw input values without adequate parameterization or escaping. This creates a classic sql injection vector where an attacker can append malicious SQL code to search terms, potentially gaining unauthorized access to database contents, modifying sensitive information, or executing destructive operations on the underlying database system.
The operational impact of this vulnerability extends beyond simple data theft, as it can enable full database compromise and potential lateral movement within affected systems. Attackers exploiting this vulnerability could extract user credentials, personal information, and other sensitive data stored in the WordPress database. The unauthenticated nature of the attack means that no prior login credentials are required to exploit the flaw, making it particularly dangerous for publicly accessible websites running vulnerable versions of the plugin. This vulnerability aligns with CWE-89 which specifically addresses SQL injection flaws and represents a significant risk to web application security.
The attack surface for this vulnerability is broad given the widespread use of WordPress and the Relevanssi Light plugin for search functionality across numerous websites. Organizations running affected versions are exposed to automated scanning tools that can identify and exploit such vulnerabilities without requiring specialized knowledge or access credentials. The potential for mass exploitation increases when considering that many website administrators may not be aware of the specific plugin version they are running, creating a large window of opportunity for attackers.
Mitigation strategies should prioritize immediate patching of the vulnerable plugin to versions that properly implement input validation and parameterized queries. System administrators should also implement web application firewalls to monitor and block suspicious SQL injection patterns targeting known vulnerable endpoints. Additional defensive measures include restricting database user privileges to minimum required permissions, implementing proper access controls for administrative interfaces, and conducting regular security audits to identify other potential injection vulnerabilities. Organizations should follow ATT&CK framework guidance for defensive techniques related to command and control communications and credential access to prevent exploitation of such vulnerabilities. Database query logging and monitoring should be implemented to detect suspicious activity patterns that may indicate exploitation attempts, while regular security updates and patch management processes should be enforced across all web application components to minimize exposure windows for similar vulnerabilities.