CVE-2026-23812 is a vulnerability in Hewlett Packard Enterprise's Aruba Networking Wireless Operating Systems versions AOS-8 and AOS-10. The flaw allows an attacker who has connected to the network as a standard wired or wireless client to impersonate the network gateway by exploiting an address-based spoofing technique. This spoofing enables the attacker to redirect data streams intended for the legitimate gateway, effectively positioning themselves as a Man-in-the-Middle (MitM). Through this MitM position, the attacker can intercept or modify network traffic, potentially capturing sensitive information or manipulating data flows. The vulnerability affects multiple versions of AOS-8 (8.10.0.0, 8.12.0.0, 8.13.0.0) and AOS-10 (10.4.0.0, 10.7.0.0, 10.8.0.0). The attack vector is adjacent network access (AV:A), meaning the attacker must be on the same network segment, but no privileges or user interaction are required. The CVSS v3.1 base score is 4.3, indicating a medium severity primarily due to limited confidentiality impact and no impact on integrity or availability. No public exploits have been reported yet, but the vulnerability poses a risk to organizations relying on HPE Aruba wireless infrastructure for secure network access. The root cause relates to insufficient validation of gateway identity, allowing address spoofing by connected clients.

The primary impact of CVE-2026-23812 is the potential interception and redirection of network traffic through a Man-in-the-Middle attack. This can lead to unauthorized disclosure of sensitive information transmitted over the network, including credentials, internal communications, or proprietary data. Although the vulnerability does not directly affect data integrity or availability, the ability to intercept traffic can facilitate further attacks such as session hijacking or injection of malicious payloads. Organizations with critical wireless infrastructure using affected HPE Aruba AOS versions may face increased risk of data leakage and network reconnaissance by malicious insiders or attackers who gain network access. The requirement for network adjacency limits remote exploitation but does not eliminate risk in environments with open or poorly segmented wireless networks. The absence of known exploits reduces immediate threat but does not preclude future weaponization. Overall, this vulnerability undermines trust in network gateway authenticity and could compromise confidentiality in sensitive enterprise environments.

To mitigate CVE-2026-23812, organizations should apply patches or firmware updates from Hewlett Packard Enterprise as soon as they become available for the affected AOS versions. In the interim, network administrators should implement strict network segmentation to separate client devices from critical gateway infrastructure, reducing the attack surface. Enabling dynamic ARP inspection (DAI) and IP source guard on switches can help detect and block address spoofing attempts. Monitoring network traffic for anomalous gateway MAC or IP addresses and unusual routing behavior can provide early detection of MitM attempts. Employing strong wireless security protocols (WPA3) and client isolation features can limit attacker access. Additionally, enforcing network access control (NAC) to authenticate and authorize devices before granting network connectivity reduces the risk of unauthorized clients exploiting this vulnerability. Regular security audits and penetration testing focused on wireless infrastructure can help identify and remediate weaknesses related to gateway spoofing.