CVE-2025-24868: SAP HANA XS Auth Bypass Vulnerability

CVE-2025-24868 Overview

CVE-2025-24868 is an Open Redirect vulnerability affecting the User Account and Authentication service (UAA) for SAP HANA extended application services, advanced model (SAP HANA XS advanced model). The vulnerability allows an unauthenticated attacker to craft a malicious link that, when clicked by a victim, redirects the browser to a malicious site due to insufficient redirect URL validation.

Critical Impact

Successful exploitation allows attackers to redirect users to malicious websites, potentially enabling phishing attacks, credential theft, or malware distribution while leveraging the trust of legitimate SAP HANA domains.

Affected Products

• SAP HANA XS Advanced Model
• SAP HANA User Account and Authentication (UAA) Service
• SAP HANA Extended Application Services

Discovery Timeline

• 2025-02-11 - CVE-2025-24868 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2025-24868

Vulnerability Analysis

This vulnerability is classified as CWE-601: URL Redirection to Untrusted Site ('Open Redirect'). The SAP HANA XS Advanced UAA service fails to properly validate redirect URLs provided in authentication requests. When a user interacts with the authentication service, the application accepts a redirect parameter that specifies where to send the user after authentication. Due to insufficient validation of this parameter, an attacker can supply an arbitrary external URL.

The attack requires user interaction—specifically, a victim must click on a crafted malicious link. Once clicked, the user's browser is redirected through the legitimate SAP HANA authentication endpoint to an attacker-controlled website. This can lead to limited impact on confidentiality, integrity, and availability of the system, as users may unknowingly submit credentials or sensitive information to fraudulent sites.

Root Cause

The root cause of this vulnerability is insufficient input validation within the UAA service's redirect URL handling logic. The application does not adequately verify that the redirect destination belongs to trusted domains or follows expected URL patterns. This allows attackers to inject arbitrary external URLs into authentication flows, bypassing intended security boundaries.

Attack Vector

The attack vector is network-based and requires no authentication. An attacker crafts a URL that includes the legitimate SAP HANA XS Advanced authentication endpoint with a manipulated redirect parameter pointing to a malicious domain. The attack flow typically involves:

1. Attacker identifies the vulnerable redirect parameter in the UAA authentication endpoint
2. Attacker constructs a URL with a legitimate SAP HANA domain but an attacker-controlled redirect destination
3. Attacker distributes the malicious link via phishing emails, social engineering, or other delivery mechanisms
4. Victim clicks the link, trusting the legitimate SAP domain in the URL
5. After authentication or immediately, the victim's browser is redirected to the attacker's malicious site

The vulnerability manifests in the authentication redirect flow of the UAA service. For technical implementation details, refer to SAP Note #3563929.

Detection Methods for CVE-2025-24868

Indicators of Compromise

• Unusual outbound redirects from SAP HANA authentication endpoints to external domains
• Authentication logs showing redirect parameters with unfamiliar or suspicious external URLs
• User reports of being redirected to unexpected websites after interacting with SAP HANA links
• Phishing campaigns leveraging legitimate SAP HANA domain URLs with malicious redirect parameters

Detection Strategies

• Monitor authentication service logs for redirect parameters containing external or non-whitelisted domains
• Implement web application firewall (WAF) rules to flag requests with suspicious redirect URL patterns
• Deploy network monitoring to identify connections to known malicious domains following SAP HANA authentication requests
• Utilize SentinelOne Singularity platform to detect and alert on anomalous redirect behaviors in protected environments

Monitoring Recommendations

• Enable detailed logging for the UAA service to capture all redirect parameter values
• Configure alerts for authentication requests containing external URLs in redirect parameters
• Regularly review authentication flow logs for patterns indicative of exploitation attempts
• Implement URL reputation checking for redirect destinations within authentication workflows

How to Mitigate CVE-2025-24868

Immediate Actions Required

• Apply the security patch referenced in SAP Note #3563929 immediately
• Review authentication configurations in SAP HANA XS Advanced environments
• Educate users about the risks of clicking links in unsolicited communications, even if they appear to originate from legitimate SAP domains
• Implement strict redirect URL validation or whitelisting as an interim measure if patching is delayed

Patch Information

SAP has released a security update to address this vulnerability. Organizations should obtain and apply the patch through the official SAP Security Patch Day portal. Detailed remediation instructions are available in SAP Note #3563929. It is essential to test the patch in a non-production environment before deploying to production systems.

Workarounds

• Implement a web application firewall (WAF) with rules to validate and restrict redirect parameters to trusted domains only
• Configure network egress filtering to block connections to suspicious or unverified external domains
• Deploy URL filtering at the proxy level to prevent redirects to known malicious sites
• Consider temporarily disabling or restricting access to affected authentication endpoints until patching is complete

# Example: WAF rule concept for redirect validation
# Note: Specific implementation varies by WAF vendor
# Whitelist only approved redirect domains in authentication flows
# Block requests where redirect parameter contains external/untrusted URLs