CVE-2026-75689: Adobe Connect Stored XSS Vulnerability

CVE-2026-75689 Overview

CVE-2026-75689 is a stored Cross-Site Scripting (XSS) vulnerability [CWE-79] affecting Adobe Connect. Attackers can inject malicious JavaScript into vulnerable form fields, which then executes in the browsers of users who view the affected pages. Successful exploitation can lead to session hijacking, account takeover, or elevated access within the Adobe Connect environment. The scope is changed, meaning the exploited component can impact resources beyond its security boundary.

Critical Impact
A network-based attacker with no prior privileges can persistently store malicious scripts that execute in victim browsers, enabling account takeover and session compromise across the Adobe Connect application.

Affected Products

Adobe Connect (refer to Adobe Security Advisory APSB26-150 for specific affected versions)

Discovery Timeline

2026-09-22 - CVE-2026-75689 published to NVD
2026-09-22 - Last updated in NVD database

Technical Details for CVE-2026-75689

Vulnerability Analysis

The vulnerability is a stored XSS flaw in Adobe Connect form fields. Adobe Connect fails to sanitize user-supplied input before persisting it and rendering it back to other users. When a victim navigates to a page containing the malicious payload, the browser executes the injected JavaScript in the context of the Adobe Connect origin.

Because the scope is changed, the impact extends beyond the vulnerable component itself. Injected scripts can access session tokens, perform actions on behalf of the victim, or pivot to adjacent application features. Exploitation requires user interaction, typically the victim loading the compromised page.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. Adobe Connect accepts user input into form fields without sufficient output encoding or input validation, allowing script tags and event handlers to persist in server-side storage and reflect into the rendered DOM.

Attack Vector

The attack is network-based and requires no authentication. An unauthenticated attacker submits crafted input containing JavaScript payloads into a vulnerable form field. The payload is stored server-side and later rendered to any user visiting the affected page. Victim interaction is limited to loading the page, at which point the payload executes with full access to the victim's Adobe Connect session context.

No verified public exploit code is available. Consult the Adobe Security Advisory APSB26-150 for vendor-supplied technical details.

Detection Methods for CVE-2026-75689

Indicators of Compromise

Unexpected <script> tags, javascript: URIs, or DOM event handlers (onerror, onload, onclick) stored in Adobe Connect form fields or database records.
Outbound requests from user browsers to attacker-controlled domains following Adobe Connect page loads.
Anomalous session token usage or account activity originating from IP addresses that recently rendered a compromised page.

Detection Strategies

Review Adobe Connect web server access logs for POST requests containing script-like payloads targeting form submission endpoints.
Deploy a web application firewall (WAF) rule set that flags common XSS payload patterns submitted to Adobe Connect input fields.
Perform database audits of stored form field content for HTML tags, encoded script fragments, or suspicious Unicode escapes.

Monitoring Recommendations

Enable Content Security Policy (CSP) violation reporting to surface unauthorized inline script execution attempts.
Correlate authentication events with page-render events to identify session anomalies indicative of token theft.
Monitor for privilege changes or unauthorized administrative actions performed by Adobe Connect user accounts.

How to Mitigate CVE-2026-75689

Immediate Actions Required

Apply the security update referenced in Adobe Security Advisory APSB26-150 as the primary remediation.
Audit existing form field data for previously injected payloads and purge malicious entries.
Rotate session tokens and require reauthentication for user accounts that may have been exposed.

Patch Information

Adobe has published fixed versions in Adobe Security Advisory APSB26-150. Administrators should consult the advisory for the exact patched build numbers applicable to their deployment and schedule an emergency change window given the CVSS 9.3 rating.

Workarounds

Restrict access to Adobe Connect to trusted networks or authenticated users via network segmentation until patches are applied.
Deploy a WAF policy that blocks HTML and JavaScript metacharacters submitted to Adobe Connect form endpoints.
Enforce a strict Content Security Policy that disallows inline scripts and unauthorized script sources on Adobe Connect pages.

bash

# Example nginx CSP header to reduce stored XSS impact
add_header Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'; frame-ancestors 'self'" always;