CVE-2026-23598: HPE Aruba 5G Core Information Disclosure

CVE-2026-23598 Overview

Vulnerabilities in the API error handling of an HPE Aruba Networking 5G Core server API could allow an unauthenticated remote attacker to obtain sensitive information. Successful exploitation could allow an attacker to access details such as user accounts, roles, and system configuration, as well as to gain insight into internal services and workflows, increasing the risk of unauthorized access and elevated privileges when combined with other vulnerabilities.

Critical Impact

Unauthenticated attackers on an adjacent network can exploit improper API error handling to obtain sensitive information including user accounts, roles, system configuration, and internal service details, potentially enabling privilege escalation when chained with other vulnerabilities.

Affected Products

• HPE Aruba Networking 5G Core Server

Discovery Timeline

• 2026-02-17 - CVE CVE-2026-23598 published to NVD
• 2026-02-18 - Last updated in NVD database

Technical Details for CVE-2026-23598

Vulnerability Analysis

This vulnerability stems from improper error handling within the HPE Aruba Networking 5G Core server API. When API requests trigger error conditions, the server generates verbose error responses that inadvertently expose sensitive internal information. This information disclosure vulnerability is particularly concerning in 5G core network environments where exposure of system configuration details could provide attackers with reconnaissance data for further attacks.

The vulnerability requires adjacent network access, meaning an attacker must have access to the same network segment as the vulnerable 5G Core server. However, no authentication is required to trigger the vulnerable error conditions, lowering the barrier to exploitation.

Root Cause

The root cause of this vulnerability lies in inadequate sanitization and filtering of error messages returned by the API. When exceptions or errors occur during API request processing, the error handling routines include excessive diagnostic information in the response body. This information leakage reveals internal system state, user account details, role configurations, and service architecture information that should remain confidential.

Attack Vector

An unauthenticated attacker positioned on an adjacent network can craft malformed or unexpected API requests to the HPE Aruba Networking 5G Core server. When these requests trigger error conditions, the verbose error responses disclose sensitive information. The attacker can systematically probe different API endpoints to enumerate user accounts, understand system roles and permissions, map internal services and workflows, and gather configuration details. This reconnaissance data can then be leveraged in combination with other vulnerabilities to achieve unauthorized access or privilege escalation.

The vulnerability manifests in the API error handling routines where exception details are exposed in HTTP responses. Technical details are available in the HPE Security Bulletin.

Detection Methods for CVE-2026-23598

Indicators of Compromise

• Unusual volume of API error responses from 5G Core server endpoints
• Repeated API requests from single sources triggering error conditions
• Network traffic analysis showing enumeration patterns against API endpoints
• Log entries indicating sequential probing of different API paths

Detection Strategies

• Monitor API access logs for patterns of requests that consistently trigger error responses
• Implement anomaly detection for unusual API request patterns from adjacent network segments
• Review HTTP response sizes for anomalously large error responses that may indicate verbose error disclosure
• Deploy network intrusion detection signatures for API enumeration behavior

Monitoring Recommendations

• Enable verbose logging on the HPE Aruba Networking 5G Core server to capture API request details
• Configure alerting for repeated authentication failures or error conditions from single sources
• Implement rate limiting and threshold-based alerts for API endpoints
• Regularly audit API access logs for suspicious reconnaissance activity

How to Mitigate CVE-2026-23598

Immediate Actions Required

• Apply the latest security patches from HPE Aruba Networking as referenced in the security bulletin
• Implement network segmentation to restrict access to the 5G Core server API to authorized systems only
• Enable API authentication and access controls where possible
• Review and harden firewall rules governing access to 5G Core infrastructure

Patch Information

HPE has released security guidance addressing this vulnerability. Administrators should consult the HPE Security Bulletin for specific patch information and update instructions. Apply the recommended updates as soon as possible following your organization's change management procedures.

Workarounds

• Restrict network access to the 5G Core API to only trusted administrative systems using firewall rules or network ACLs
• Implement a web application firewall (WAF) or API gateway to filter and sanitize API error responses before they reach clients
• Enable API rate limiting to slow down potential enumeration attempts
• Consider placing the 5G Core server behind a reverse proxy that masks detailed error information

# Example network ACL configuration to restrict API access
# Restrict 5G Core API access to management VLAN only
iptables -A INPUT -p tcp --dport 443 -s 10.0.100.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP