CVE-2026-4772: WAF-ASP Stored XSS Vulnerability

CVE-2026-4772 Overview

CVE-2026-4772 is a stored cross-site scripting (XSS) vulnerability affecting TR7 Cyber Defense Inc. WAF-ASP. The flaw stems from improper neutralization of user-supplied input during web page generation, allowing attackers to inject persistent malicious scripts into the application. The vulnerability is classified under [CWE-79] and impacts WAF-ASP versions from v1.0.324.900 before v1.4.0.117. Exploitation requires low-privilege authentication and user interaction, but the scope is changed, meaning injected scripts can affect components beyond the initial vulnerable context.

Critical Impact
Authenticated attackers can inject persistent JavaScript payloads that execute in the browsers of other users, enabling session hijacking, credential theft, and unauthorized actions within the WAF-ASP management interface.

Affected Products

TR7 Cyber Defense Inc. WAF-ASP v1.0.324.900 through versions prior to v1.4.0.117
Web-based management components of WAF-ASP that render user-supplied input
Deployments exposing the WAF-ASP administrative interface to authenticated users

Discovery Timeline

2026-07-02 - CVE-2026-4772 published to NVD
2026-07-02 - Last updated in NVD database

Technical Details for CVE-2026-4772

Vulnerability Analysis

The vulnerability exists in the WAF-ASP web interface where user-controlled input is stored server-side and later rendered into HTML responses without adequate output encoding or sanitization. When an authenticated attacker submits crafted input containing HTML or JavaScript, the payload persists in the application's data store. Subsequent users who load the affected page trigger execution of the attacker's script within their browser context.

Stored XSS is more impactful than reflected variants because payloads execute automatically for every user who views the affected content. In a WAF product context, this exposes administrators and security operators who routinely access management dashboards to monitor policy state and traffic logs.

The attack requires user interaction, meaning a victim must load the page containing the stored payload. Because the scope changes upon exploitation, the injected script can influence resources outside the initially exploited security boundary, increasing the reach of the attack against interconnected components.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. WAF-ASP fails to encode or sanitize user-supplied data before embedding it into HTML output. Neither contextual output encoding nor input validation is enforced on the affected fields, allowing raw script content to reach the DOM.

Attack Vector

An authenticated attacker with low privileges submits a crafted request containing malicious script content through an input field processed by WAF-ASP. The payload is stored server-side. When another authenticated user, typically an administrator, navigates to the page rendering that data, the browser parses and executes the injected script. The attacker can exfiltrate session tokens, perform cross-site actions on behalf of the victim, or pivot to additional interface components.

Detailed technical information is available in the Siber Güvenlik Notification TR-26-0487.

Detection Methods for CVE-2026-4772

Indicators of Compromise

Stored records within WAF-ASP containing HTML tags such as <script>, <img onerror=>, or <svg onload=> in fields that should hold plain text
Outbound HTTP requests from administrator browsers to unfamiliar domains shortly after loading WAF-ASP management pages
Unexpected session token access, cookie theft attempts, or CSRF-style actions performed under administrator accounts
Web server logs showing POST requests with encoded script payloads targeting WAF-ASP input endpoints

Detection Strategies

Review WAF-ASP database and configuration stores for entries containing HTML or JavaScript syntax in text-only fields
Deploy Content Security Policy (CSP) monitoring to detect blocked inline script execution within the WAF-ASP interface
Correlate authentication events with anomalous administrative actions occurring immediately after page loads
Inspect browser DevTools network traces during WAF-ASP interface use for unexpected script sources or beaconing behavior

Monitoring Recommendations

Enable verbose access logging on WAF-ASP management endpoints and forward logs to a centralized SIEM for analysis
Alert on any WAF-ASP input submissions containing common XSS signatures such as <script, javascript:, or onerror=
Track administrator session activity for concurrent sessions or geolocation anomalies indicating token theft

How to Mitigate CVE-2026-4772

Immediate Actions Required

Upgrade WAF-ASP to version v1.4.0.117 or later, which addresses the input neutralization defect
Restrict access to the WAF-ASP management interface to trusted administrative networks only
Rotate administrative credentials and session tokens after patching to invalidate any material captured via prior exploitation
Audit stored WAF-ASP records for pre-existing malicious payloads and remove any suspicious entries

Patch Information

TR7 Cyber Defense Inc. addresses CVE-2026-4772 in WAF-ASP v1.4.0.117. Administrators running any version from v1.0.324.900 up to but not including v1.4.0.117 must upgrade. Refer to the Siber Güvenlik Notification TR-26-0487 for vendor-specific update guidance.

Workarounds

Limit WAF-ASP administrative account creation and enforce least-privilege role assignments until patching completes
Deploy a reverse proxy or upstream WAF rule that inspects and blocks payloads containing HTML or script tokens targeting WAF-ASP endpoints
Enforce a strict Content Security Policy that disallows inline scripts and untrusted script sources for the WAF-ASP interface
Require multi-factor authentication for all WAF-ASP administrative accounts to reduce the impact of session theft

bash

# Example CSP header to reduce XSS impact on the WAF-ASP interface
Content-Security-Policy: default-src 'self'; \
  script-src 'self'; \
  object-src 'none'; \
  base-uri 'self'; \
  frame-ancestors 'none'