CVE-2021-27558 in ZenTao
Summary
by MITRE • 08/31/2021
A cross site scripting (XSS) issue in EasyCorp ZenTao 12.5.3 allows remote attackers to execute arbitrary web script via various areas such as data-link-creator.
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Analysis
by VulDB Data Team • 09/03/2021
The vulnerability identified as CVE-2021-27558 represents a critical cross site scripting flaw within EasyCorp ZenTao version 12.5.3, a popular project management and issue tracking platform. This vulnerability stems from inadequate input validation and output encoding mechanisms that fail to properly sanitize user-supplied data before rendering it within web pages. The issue specifically affects the data-link-creator functionality and other related areas where user input is processed and displayed without sufficient security controls.
The technical exploitation of this vulnerability occurs when remote attackers inject malicious script code through input fields or parameters that are subsequently rendered in web pages without proper sanitization. This allows attackers to execute arbitrary web scripts within the context of a victim's browser session, potentially enabling session hijacking, credential theft, or redirection to malicious websites. The vulnerability manifests across multiple attack vectors within the application's interface, making it particularly dangerous as attackers can leverage various entry points to deliver their payloads. The flaw directly maps to CWE-79 - Cross-site Scripting, which is classified as a critical weakness in web application security.
From an operational impact perspective, this vulnerability compromises the security posture of organizations using ZenTao 12.5.3 by potentially allowing unauthorized access to sensitive project data, user credentials, and system resources. Attackers could exploit this flaw to escalate privileges, modify project information, or gain persistent access to the application through session manipulation. The vulnerability's remote nature means that attackers do not require physical access to the system and can exploit it from anywhere on the internet, making it particularly attractive for automated attacks. Organizations relying on this platform for project management and collaboration face significant risk of data breaches and operational disruption.
Security mitigations for this vulnerability should include immediate patching of the ZenTao platform to version 12.5.4 or later, which contains the necessary fixes for input validation and output encoding. Organizations should also implement comprehensive input sanitization measures, including the use of context-specific output encoding for all user-supplied data. 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 assessments and penetration testing should be conducted to identify similar vulnerabilities in other components of the application stack. The remediation process should follow established security frameworks such as those outlined in the OWASP Top Ten and NIST Cybersecurity Framework, ensuring that the fix addresses the root cause rather than merely patching symptoms. Implementation of proper content security policies and regular security training for developers can help prevent similar issues in future development cycles.