CVE-2023-41013 in IceWarp
Summary
by MITRE • 09/12/2023
Cross Site Scripting (XSS) in Webmail Calendar in IceWarp 10.3.1 allows remote attackers to inject arbitrary web script or HTML via the "p4" field.
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Analysis
by VulDB Data Team • 01/30/2026
The vulnerability CVE-2023-41013 represents a critical cross site scripting flaw within the IceWarp Webmail Calendar component version 10.3.1. This issue affects the web-based email and calendar system developed by IceWarp, which is widely deployed in enterprise environments for unified communications. The vulnerability specifically resides in the calendar functionality where user input is not properly sanitized before being rendered back to users, creating an avenue for malicious actors to execute arbitrary code within the context of a victim's browser session.
The technical exploitation occurs through the "p4" field parameter which serves as an entry point for attackers to inject malicious scripts. When an attacker crafts a specially formatted payload and submits it through this field, the application fails to validate or escape the input before displaying it in the calendar interface. This allows the injected script to execute in the browser context of any user who views the affected calendar entry, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability is classified as a classic reflected XSS attack pattern where the malicious payload is reflected back to the user through the application's response without proper sanitization.
From an operational standpoint, this vulnerability poses significant risks to organizations relying on IceWarp for their communication infrastructure. Attackers could exploit this weakness to gain unauthorized access to calendar data, schedule meetings with malicious links, or manipulate calendar entries to spread malware. The impact extends beyond simple data exposure as the vulnerability could be leveraged for more sophisticated attacks including phishing campaigns where users are tricked into executing malicious code under the guise of legitimate calendar notifications. This particular vulnerability affects the webmail calendar functionality specifically, making it a targeted attack vector for social engineering and credential harvesting operations.
Organizations should implement immediate mitigations including input validation and output encoding for all user-supplied data in calendar fields, particularly the "p4" parameter mentioned in the vulnerability description. The recommended approach aligns with CWE-79 which categorizes cross site scripting vulnerabilities and follows the principle of least privilege in input handling. Security teams should also consider implementing content security policies that restrict script execution and monitor for unusual calendar activity patterns. Additionally, the vulnerability demonstrates the importance of regular security assessments and prompt patch management, as this issue affects version 10.3.1 specifically and likely represents a regression or oversight in the application's security hardening process. The ATT&CK framework categorizes this vulnerability under T1566 for initial access through malicious content, making it a potential entry point for broader network compromise operations. Organizations should prioritize updating to the latest IceWarp version that addresses this vulnerability while implementing network monitoring to detect exploitation attempts.