CVE-2025-42969: SAP NetWeaver ABAP XSS Vulnerability

CVE-2025-42969 Overview

CVE-2025-42969 is a reflected Cross-Site Scripting (XSS) vulnerability [CWE-79] affecting SAP NetWeaver Application Server ABAP and ABAP Platform. An unauthenticated attacker can inject a malicious script into a dynamically crafted URL. When a victim clicks the crafted link, the payload executes within their browser session under the SAP application's origin.

Critical Impact
Successful exploitation allows attackers to read or modify sensitive information within the scope of the victim's browser session, including session data and rendered content on the SAP NetWeaver application.

Affected Products

SAP NetWeaver Application Server ABAP
SAP ABAP Platform
Web-facing SAP NetWeaver components processing URL parameters without proper output encoding

Discovery Timeline

2025-07-08 - CVE-2025-42969 published to NVD
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2025-42969

Vulnerability Analysis

The vulnerability is a reflected XSS flaw in SAP NetWeaver Application Server ABAP and ABAP Platform. The application constructs URLs dynamically using attacker-controlled input and reflects that input into HTTP responses without adequate output encoding. An attacker crafts a URL containing a JavaScript payload and delivers it to victims via phishing or other social engineering channels. When the victim's browser renders the response, the injected script executes in the context of the trusted SAP domain.

The attack requires user interaction, no authentication, and results in a scope change because injected script runs in the victim's browser under the SAP application's security context. The confidentiality and integrity impacts are limited to data accessible within the victim's session.

Root Cause

The root cause is improper neutralization of input during web page generation [CWE-79]. SAP NetWeaver components reflect user-supplied URL parameters into HTML output without applying context-aware output encoding. Script tags, event handlers, and JavaScript URIs supplied in query parameters are rendered as executable code in the response.

Attack Vector

Exploitation follows a standard reflected XSS chain. An unauthenticated attacker crafts a URL targeting a vulnerable SAP NetWeaver endpoint and embeds a JavaScript payload in a reflected parameter. The attacker distributes the URL through email, chat, or web content. When a victim clicks the link, the SAP application returns a response containing the unescaped payload, and the browser executes the script. The attacker can then read DOM content, exfiltrate session tokens accessible to script, submit forged requests on behalf of the victim, or redirect the browser.

No verified public exploit code is available. Refer to the SAP Note #3596987 for technical details.

Detection Methods for CVE-2025-42969

Indicators of Compromise

HTTP request logs on SAP NetWeaver containing URL parameters with <script>, javascript:, onerror=, onload=, or encoded variants such as %3Cscript%3E
Referer headers pointing to external phishing domains preceding user sessions on SAP endpoints
Unexpected outbound requests from user browsers immediately after visiting SAP URLs, indicating token exfiltration
Anomalous SAP session activity originating from valid user sessions shortly after suspicious URL visits

Detection Strategies

Inspect SAP Internet Communication Manager (ICM) and web dispatcher logs for query strings containing HTML or JavaScript metacharacters
Deploy Web Application Firewall (WAF) rules that flag reflected XSS payload patterns targeting SAP paths
Correlate email gateway URL telemetry with SAP NetWeaver access logs to identify phishing-delivered exploit URLs

Monitoring Recommendations

Enable full HTTP request logging on SAP NetWeaver and forward to a centralized SIEM for pattern analysis
Monitor Content Security Policy (CSP) violation reports if CSP is configured on SAP web endpoints
Alert on user reports of unexpected browser behavior or session termination following SAP URL clicks

How to Mitigate CVE-2025-42969

Immediate Actions Required

Apply the SAP security patch referenced in SAP Note #3596987 to all NetWeaver ABAP and ABAP Platform systems
Review the SAP Security Patch Day advisories to confirm the fix level required for your release
Notify end users to avoid clicking untrusted URLs pointing to SAP hostnames until patching is complete

Patch Information

SAP has released a fix documented in SAP Note #3596987. Administrators must authenticate to the SAP Support Portal to retrieve the patch and apply it according to the note's implementation instructions. Confirm the corrected component version after applying the patch and validate remediation in a non-production system before rolling out to production.

Workarounds

Deploy WAF signatures that block requests containing script tags, event handler attributes, and JavaScript URIs in query parameters directed at SAP endpoints
Configure a strict Content Security Policy on SAP web responses to restrict inline script execution
Restrict external access to SAP NetWeaver interfaces via network segmentation and VPN until the patch is applied

bash

# Example WAF rule concept (ModSecurity syntax) - adapt to your environment
SecRule ARGS "@rx (?i)(<script|javascript:|onerror=|onload=)" \
  "id:1042969,phase:2,deny,status:403,\
   msg:'Potential XSS targeting SAP NetWeaver (CVE-2025-42969)'"