CVE-2026-0510: NetWeaver AS Java Info Disclosure Flaw

CVE-2026-0510 Overview

CVE-2026-0510 affects the User Management Engine (UME) in SAP NetWeaver Application Server for Java (NW AS Java). The component uses an obsolete cryptographic algorithm to encrypt User Mapping data. An attacker with high-privileged access can exploit this weakness under specific conditions to obtain partial disclosure of sensitive information. The flaw is classified under CWE-326 (Inadequate Encryption Strength). The vulnerability impacts confidentiality only, with no impact on integrity or availability. SAP addressed the issue through SAP Security Patch Day guidance and an associated SAP Note.

Critical Impact
A high-privileged attacker can partially recover sensitive User Mapping data protected by the obsolete cipher in SAP NetWeaver AS Java UME.

Affected Products

SAP NetWeaver Application Server for Java (NW AS Java)
SAP User Management Engine (UME)
SAP User Mapping subsystem within UME

Discovery Timeline

2026-01-13 - CVE-2026-0510 published to NVD
2026-04-15 - Last updated in NVD database

Technical Details for CVE-2026-0510

Vulnerability Analysis

The User Management Engine in SAP NetWeaver AS Java stores User Mapping data, which links external system credentials to SAP user identities for single sign-on and federated access. The UME encrypts this data before persisting it. CVE-2026-0510 exists because the encryption relies on an obsolete cryptographic algorithm that no longer meets modern strength requirements. An attacker who already holds high-privileged access on the NetWeaver Java stack can leverage this weakness to recover portions of the protected User Mapping content. The disclosure is partial rather than complete, which constrains the practical impact but still exposes credential material and account associations that should remain confidential.

Root Cause

The root cause is the continued use of a deprecated cipher for at-rest protection of User Mapping records inside UME. Cryptographic algorithms degrade over time as cryptanalysis advances and computing power grows. When a product retains a legacy algorithm beyond its useful life, ciphertext that was previously considered safe becomes recoverable under specific conditions. This is the pattern captured by CWE-326, Inadequate Encryption Strength.

Attack Vector

Exploitation requires network access to the NetWeaver Java instance and high privileges on the platform, with no user interaction. The attack complexity is high because the attacker must reach the encrypted User Mapping data and meet the specific conditions referenced by SAP. The scope is changed, meaning successful exploitation affects resources beyond the vulnerable component itself. Refer to SAP Note #3593356 and the SAP Security Patch Day Announcement for the authoritative technical details.

Detection Methods for CVE-2026-0510

Indicators of Compromise

No public indicators of compromise are associated with CVE-2026-0510 at the time of writing.
Unexpected administrator-level access to UME configuration or User Mapping export functions should be treated as suspicious.
Anomalous reads of UME database tables that store User Mapping ciphertext warrant review.

Detection Strategies

Audit UME administrative actions and User Mapping management activity through SAP NetWeaver Java security audit logs.
Monitor for use of administrative tools such as the User Management Engine console and Visual Administrator by accounts that do not normally perform identity management.
Correlate high-privilege NW AS Java sessions with subsequent access to User Mapping storage.

Monitoring Recommendations

Forward SAP NetWeaver Java audit logs to a centralized analytics platform for retention and correlation.
Alert on privilege changes that grant UME administrative roles or UME.Manage_All style authorizations.
Track configuration changes to UME cryptographic settings after applying the SAP patch.

How to Mitigate CVE-2026-0510

Immediate Actions Required

Apply the corrections described in SAP Note #3593356 on all affected NetWeaver AS Java systems.
Review and minimize the set of accounts holding high privileges on NW AS Java, especially UME administrative roles.
Re-encrypt or rotate User Mapping entries after patching so legacy ciphertext is replaced with data protected by the updated algorithm.

Patch Information

SAP published the fix as part of SAP Security Patch Day. Customers should consult SAP Note #3593356 for the specific support package, kernel patch, or manual correction applicable to their NetWeaver AS Java release. The SAP Security Patch Day Announcement lists the release context for this advisory.

Workarounds

Restrict network reachability of NetWeaver AS Java administrative interfaces to trusted management networks.
Enforce strict separation of duties so that no single account combines UME administration with access to underlying database storage.
Where User Mapping is not required, disable the feature or remove stored mappings to reduce exposure until patching completes.

bash

# Configuration example
# Restrict UME administrative endpoints at the reverse proxy / load balancer
# Replace with your trusted management CIDR
allow  10.0.10.0/24;   # management subnet
deny   all;            # everything else blocked from /useradmin and /irj/portal admin paths