CVE-2025-2536: Liferay DXP XSS Vulnerability

CVE-2025-2536 Overview

CVE-2025-2536 is a reflected cross-site scripting (XSS) vulnerability affecting Liferay Portal and Liferay Digital Experience Platform (DXP). The flaw resides in the Frontend JS module at layout-taglib/__liferay__/index.js, where the toastData parameter is rendered without proper sanitization. Remote attackers can inject arbitrary HTML or JavaScript that executes in the context of a victim's browser session.

The vulnerability is categorized under [CWE-79] Improper Neutralization of Input During Web Page Generation. Exploitation requires user interaction, typically by convincing a target to click a crafted link. Successful exploitation can lead to session token theft, credential harvesting, or unauthorized actions performed on behalf of authenticated portal users.

Critical Impact

Attackers can execute arbitrary script in a victim's browser via the toastData parameter, enabling session hijacking, phishing overlays, and unauthorized actions inside Liferay Portal and DXP deployments.

Affected Products

• Liferay Portal 7.4.3.82 through 7.4.3.128
• Liferay DXP 7.4 update 82 through update 92
• Liferay DXP 2023.Q3.1 through 2023.Q3.10, 2023.Q4.0 through 2023.Q4.10, 2024.Q1.1 through 2024.Q1.12, 2024.Q2.0 through 2024.Q2.13, and 2024.Q3.0

Discovery Timeline

• 2025-03-19 - CVE-2025-2536 published to NVD
• 2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-2536

Vulnerability Analysis

The vulnerability exists in Liferay's Frontend JS module, specifically in the layout-taglib/__liferay__/index.js component. This module is responsible for rendering toast notifications within the portal interface. The toastData parameter passed to this module is consumed and rendered into the DOM without sufficient output encoding or sanitization.

An attacker crafts a URL or request containing malicious script content in the toastData parameter. When a Liferay user follows the link or triggers the vulnerable flow, the payload is reflected into the page and executed by the browser. The attack runs with the privileges of the current portal session, granting the attacker access to any actions available to that user.

Root Cause

The root cause is missing input sanitization and output encoding on the toastData parameter within the layout-taglib frontend module. Data supplied through this parameter is treated as trusted markup rather than untrusted user input. Because Liferay Portal exposes this module across authenticated and unauthenticated flows, the vulnerability surface extends to any user who can be tricked into loading a crafted URL.

Attack Vector

Exploitation occurs over the network and requires user interaction (UI:A). An attacker constructs a URL targeting a vulnerable Liferay endpoint with a malicious toastData payload, then delivers it through email, chat, or a compromised web page. When the victim visits the link while authenticated, the injected script runs in the portal origin and can steal cookies, session tokens, or CSRF tokens, or perform actions on behalf of the user.

No verified public proof-of-concept has been released. Refer to the Liferay Known Vulnerabilities Advisory for vendor-supplied technical details.

Detection Methods for CVE-2025-2536

Indicators of Compromise

• HTTP requests to Liferay endpoints containing toastData parameters with encoded <script>, onerror=, onload=, or javascript: payload fragments.
• Unexpected outbound requests from browser sessions to attacker-controlled domains immediately after a user loads a Liferay URL.
• Web server access logs showing unusually long or URL-encoded toastData query values from external referrers.

Detection Strategies

• Deploy web application firewall (WAF) rules that inspect and block script-like patterns in the toastData query and body parameter on Liferay routes.
• Correlate Liferay access logs with browser telemetry to identify sessions where a suspicious toastData value preceded anomalous authenticated actions.
• Review Content Security Policy (CSP) violation reports for inline script blocks originating from Liferay-served pages.

Monitoring Recommendations

• Monitor Liferay application and reverse proxy logs for repeated requests containing the toastData parameter from the same source IP.
• Alert on session token or cookie exfiltration patterns following Liferay page loads, including anomalous document.cookie access in browser telemetry.
• Track admin and privileged account activity for actions taken shortly after a user clicks an externally sourced Liferay link.

How to Mitigate CVE-2025-2536

Immediate Actions Required

• Upgrade Liferay Portal to a fixed release beyond 7.4.3.128 and Liferay DXP to a patched quarterly release as documented in the vendor advisory.
• Apply the DXP hotfix for 7.4 update 92 and any subsequent security fix pack published by Liferay.
• Restrict administrative Liferay interfaces to trusted networks or VPN access while patching is scheduled.

Patch Information

Liferay has published remediation guidance in the Liferay Known Vulnerabilities Advisory for CVE-2025-2536. Administrators should follow the fix pack instructions matching their deployed branch (7.4 GA, DXP 7.4 updates, or quarterly DXP releases from 2023.Q3 through 2024.Q3).

Workarounds

• Deploy a WAF rule that strips or blocks HTML control characters (<, >, ", ') in the toastData parameter for all Liferay routes.
• Enforce a strict Content Security Policy that disallows inline scripts and restricts script sources to trusted origins.
• Enable the HttpOnly and SameSite=Strict flags on Liferay session cookies to reduce the impact of successful script execution.

# Example WAF rule (ModSecurity) to block script payloads in toastData
SecRule ARGS:toastData "@rx (?i)(<script|onerror=|onload=|javascript:)" \
    "id:1002536,phase:2,deny,status:403,\
     msg:'CVE-2025-2536 Liferay toastData XSS attempt blocked',\
     tag:'CVE-2025-2536',tag:'xss'"