CVE-2021-44467 is a medium severity vulnerability classified under CWE-284 (Improper Access Control) affecting the Lanner Inc IAC-AST2500A device running standard firmware version 1.10.0. The vulnerability exists in the KillDupUsr_func function of the spx_restservice component. Specifically, an attacker who can correctly guess a particular input parameter can exploit this flaw to arbitrarily terminate active sessions of other users. This results in a Denial-of-Service (DoS) condition by disrupting legitimate user sessions. The vulnerability does not require authentication or user interaction and can be exploited remotely over the network (AV:N, PR:N, UI:N). The CVSS v3.1 base score is 5.3, reflecting a medium severity level primarily due to the impact being limited to availability (A:L) without affecting confidentiality or integrity. No known exploits are currently reported in the wild, and no patches have been linked or published yet. The root cause is improper access control that allows unauthorized session termination, which could be leveraged by attackers to disrupt operations or cause service interruptions on affected devices.

For European organizations using Lanner Inc IAC-AST2500A devices with firmware version 1.10.0, this vulnerability poses a risk of service disruption through denial-of-service attacks. Since the device is likely used in industrial, networking, or infrastructure contexts, arbitrary termination of user sessions could interrupt critical management or monitoring functions. This could degrade operational continuity, delay incident response, or cause temporary loss of control over affected systems. Although confidentiality and integrity are not directly impacted, availability interruptions can have cascading effects on business processes, especially in sectors relying on real-time data or control systems. The ease of exploitation without authentication increases the risk profile, particularly for organizations with exposed management interfaces accessible from less trusted networks. The absence of known exploits suggests limited active targeting so far, but the vulnerability should be addressed promptly to prevent potential abuse.

Organizations should immediately assess their deployment of Lanner Inc IAC-AST2500A devices to identify those running firmware version 1.10.0. Until an official patch is available, the following mitigations are recommended: 1) Restrict network access to the spx_restservice interface using network segmentation, firewalls, or access control lists to limit exposure to trusted management networks only. 2) Implement strong monitoring and alerting on session termination events to detect unusual or unauthorized activity promptly. 3) Employ VPNs or other secure remote access methods to reduce the attack surface. 4) Engage with Lanner Inc support channels to obtain firmware updates or patches as soon as they become available. 5) Consider temporary operational controls such as limiting concurrent sessions or enforcing session timeouts to reduce the impact of forced session terminations. 6) Conduct regular security audits and penetration testing focused on access control mechanisms of management interfaces to identify similar weaknesses.