CVE-2026-91024 in Booking Manager Plugin
Summary
by MITRE • 09/23/2026
The Booking Manager WordPress plugin before 2.1.21 does not sanitize and escape values taken from a fetched external iCalendar feed before using them in a SQL query, allowing authenticated users with Author-level access and above to perform SQL injection attacks by importing a feed they control.
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Analysis
by VulDB Data Team • 09/23/2026
The vulnerability identified in the Booking Manager WordPress plugin prior to version 2.1.21 represents a critical security flaw rooted in insufficient input validation and output encoding mechanisms. Specifically, the application fails to properly sanitize or escape data retrieved from external iCalendar feeds before incorporating that data into SQL queries executed against the underlying database. This architectural oversight creates a direct pathway for attackers to manipulate backend database operations through maliciously crafted calendar entries. The core technical deficiency lies in the lack of parameterized query usage and the absence of rigorous type checking on user-supplied input derived from third-party sources, which are treated with less scrutiny than native form inputs despite posing equivalent risks when processed by dynamic SQL construction logic.
From an operational perspective, this flaw allows authenticated users possessing Author-level access or higher to execute arbitrary Structured Query Language commands within the context of the web application process. By importing a controlled iCalendar feed containing specially crafted event data, such as titles, descriptions, or date fields embedded with SQL syntax, these privileged actors can bypass standard authentication checks inherent in the plugin's import functionality. The attacker leverages this capability to interact directly with the database server, potentially extracting sensitive information such as administrator credentials, user session tokens, or proprietary business data stored within the WordPress installation. Furthermore, depending on the specific configuration and privileges of the database account running the web application, an attacker could modify existing records, delete critical entries, or in severe cases execute operating system commands if the database service permits it, thereby achieving full compromise of the hosting environment.
This vulnerability aligns with Common Weakness Enumeration identifier CWE-89, which classifies improper neutralization of special elements used in a SQL command, commonly known as SQL injection. The attack vector is categorized under MITRE ATT&CK technique T1059, specifically Command and Scripting Interpreter subcategories related to database commands, reflecting the method by which an adversary interacts with backend systems through injected payloads. Additionally, it relates to CWE-20, improper input validation, highlighting the failure of the application to adequately verify or transform external data before processing. The presence of this flaw underscores a broader industry challenge where plugins that handle third-party integrations often neglect to apply the same level of security rigor as native user inputs, assuming external feeds are inherently safe when they may be manipulated by malicious actors controlling their own calendars.
To mitigate this risk, immediate action is required to update the Booking Manager plugin to version 2.1.21 or later, where these sanitization and escaping mechanisms have been corrected. In environments where updating is not immediately feasible, administrators should restrict access to the import functionality to trusted sources only and consider implementing Web Application Firewall rules that detect SQL injection patterns within calendar feed imports. Database-level monitoring can also be employed to identify anomalous query structures originating from the WordPress application process. Long-term remediation involves adopting secure coding practices such as using prepared statements with parameterized queries for all database interactions, ensuring that no user-controlled data is ever concatenated directly into SQL strings regardless of its source. Regular security audits and static code analysis tools should be integrated into the development lifecycle to detect similar vulnerabilities in other plugins or custom themes before they are deployed to production environments.