CVE-2023-23326 in AvantFAX
Summary
by MITRE • 03/11/2023
A Stored Cross-Site Scripting (XSS) vulnerability exists in AvantFAX 3.3.7. An authenticated low privilege user can inject arbitrary Javascript into their e-mail address which is executed when an administrator logs into AvantFAX to view the admin dashboard. This may result in stealing an administrator's session cookie and hijacking their session.
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Analysis
by VulDB Data Team • 10/07/2025
The CVE-2023-23326 vulnerability represents a critical stored cross-site scripting flaw in AvantFAX version 3.3.7 that demonstrates how seemingly minor input validation weaknesses can lead to significant administrative compromise. This vulnerability specifically affects the email address field within the application's user management system, where unfiltered user input is directly rendered in the administrator dashboard without proper sanitization or encoding mechanisms. The flaw exists because the application fails to implement adequate input validation and output encoding for email addresses entered by users, creating a persistent vector for malicious script injection that remains active until the affected data is explicitly removed or modified.
The technical exploitation of this vulnerability requires an authenticated user with low privilege access to the system, typically a regular user account that can modify their own profile information. When such a user enters malicious javascript code into their email address field, the script becomes permanently stored within the application's database. Upon administrative login to view the dashboard, the stored script executes in the context of the administrator's browser session, leveraging the elevated privileges of the logged-in user. This particular variant of XSS operates through a stored payload mechanism rather than reflected or DOM-based variants, making it particularly dangerous as the malicious code persists and executes automatically whenever the vulnerable page is accessed.
The operational impact of this vulnerability extends far beyond simple script execution, as it provides attackers with the capability to hijack administrative sessions and potentially gain complete control over the AvantFAX system. Session cookie theft represents the primary attack vector, allowing unauthorized parties to impersonate administrators and perform privileged actions such as modifying user accounts, accessing sensitive documents, changing system configurations, or even executing arbitrary commands within the application's environment. The vulnerability's persistence means that even if the initial injection occurs during a brief period of system access, the malicious code continues to execute whenever administrators view the dashboard, creating a continuous threat vector that can persist for months or years without detection.
Security professionals should recognize this vulnerability as a classic example of CWE-79: Improper Neutralization of Input During Web Page Generation, which falls under the broader category of web application security flaws that affect user input handling and output encoding. The attack pattern aligns with ATT&CK technique T1566.001: Phishing, where the initial compromise occurs through the manipulation of user account data rather than traditional phishing vectors. Mitigation strategies must include immediate implementation of proper input sanitization and output encoding mechanisms, such as HTML entity encoding of user-supplied email addresses before rendering them in the dashboard interface. Organizations should also implement regular input validation checks, consider implementing content security policies, and establish monitoring procedures to detect unusual patterns in user account modifications. The most effective remediation involves upgrading to a patched version of AvantFAX or implementing application-level protections that prevent script injection regardless of user input, ensuring that all user-supplied data is properly escaped or validated before being processed or displayed in administrative contexts.