CVE-2022-2844 in Timetable and Event Schedule
Summary
by MITRE • 08/16/2022
A vulnerability classified as problematic has been found in MotoPress Timetable and Event Schedule up to 1.4.06. This affects an unknown part of the file /wp/?cpmvc_id=1&cpmvc_do_action=mvparse&f=datafeed&calid=1&month_index=1&method=adddetails&id=2 of the component Calendar Handler. The manipulation of the argument Subject/Location/Description leads to cross site scripting. It is possible to initiate the attack remotely. The associated identifier of this vulnerability is VDB-206487.
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Analysis
by VulDB Data Team • 09/17/2022
This cross site scripting vulnerability exists in MotoPress Timetable and Event Schedule plugin version 1.4.06 and earlier, affecting WordPress installations through a specifically crafted request to the calendar handler component. The vulnerability manifests when user-supplied data is improperly handled during the processing of calendar events, particularly in the Subject/Location/Description fields that are processed through the mvparse action handler. The attack vector is remote, meaning an unauthenticated attacker can exploit this flaw without requiring any prior access to the system. The vulnerability resides in the datafeed processing functionality where calendar identifiers and event details are manipulated, creating a pathway for malicious script injection into web pages viewed by other users. This represents a classic reflected cross site scripting vulnerability where malicious input is directly reflected back to users without proper sanitization or encoding.
The technical implementation of this vulnerability stems from insufficient input validation and output sanitization within the calendar handler component. When the system processes the cpmvc_id parameter with value 1 and executes the mvparse action, the f=datafeed parameter triggers the datafeed processing logic that fails to properly escape or validate user-supplied values in the Subject/Location/Description fields. The method=adddetails parameter combined with the calid=1 and month_index=1 parameters creates a context where the id=2 parameter's value is processed without adequate security controls. This allows an attacker to inject malicious scripts that execute in the context of other users' browsers when they view calendar events containing the malicious data. The vulnerability specifically affects the calendar handler's processing of event metadata fields, which are rendered directly in the user interface without proper HTML entity encoding or script sanitization.
The operational impact of this vulnerability extends beyond simple script execution as it can enable attackers to perform session hijacking, deface websites, steal sensitive information from authenticated users, or redirect users to malicious sites. An attacker could craft malicious calendar events with embedded scripts that target logged-in administrators or regular users, potentially escalating privileges or accessing sensitive data. The vulnerability's remote exploitation capability means that attackers can target any WordPress site running the affected plugin version without requiring local access or authentication. This makes it particularly dangerous in multi-user environments where calendar data is shared and viewed by multiple parties. The attack could be amplified through social engineering tactics where attackers create seemingly legitimate calendar events that contain malicious payloads, leading to widespread compromise across the affected user base.
Mitigation strategies should focus on immediate plugin updates to version 1.4.07 or later where the vulnerability has been patched. Organizations should implement proper input validation and output encoding for all calendar-related data fields, particularly in the Subject/Location/Description parameters. The implementation should follow secure coding practices including the use of context-appropriate escaping functions and validation of all user-supplied input before processing. Network-level protections such as web application firewalls can provide additional defense in depth, though they should not be relied upon as the sole mitigation. Regular security audits of WordPress plugins should be conducted to identify and remediate similar vulnerabilities. This vulnerability aligns with CWE-79 which describes cross site scripting flaws, and maps to ATT&CK technique T1566.001 for social engineering via spearphishing attachments, particularly when considering how attackers might exploit this vulnerability through calendar event manipulation. System administrators should also consider implementing Content Security Policy headers to limit script execution and reduce the impact of successful XSS attacks. The vulnerability demonstrates the importance of proper input sanitization and output encoding in web applications, particularly those handling user-generated content in calendar and scheduling systems.