CVE-2026-2192 is a stack-based buffer overflow vulnerability identified in the Tenda AC9 router firmware version 15.03.06.42_multi. The flaw exists in the formGetRebootTimer function, which processes the sys.schedulereboot.start_time and sys.schedulereboot.end_time parameters. Improper validation or sanitization of these inputs allows an attacker to craft malicious arguments that overflow the stack buffer, potentially overwriting control data such as return addresses. This can lead to arbitrary code execution or denial of service on the affected device. The vulnerability is remotely exploitable over the network without user interaction, but requires high privileges, indicating that the attacker must already have some level of authenticated access or be able to bypass authentication mechanisms. The CVSS 4.0 score of 8.6 reflects the high impact on confidentiality, integrity, and availability, combined with low attack complexity and no user interaction needed. Although no exploits are currently reported in the wild, the public disclosure increases the risk of exploitation by threat actors. The affected product, Tenda AC9, is a popular consumer and small business router model, often deployed in home and small office networks. The lack of an official patch link suggests that vendors or users should monitor for firmware updates or apply interim mitigations. This vulnerability could be leveraged to gain persistent control over network infrastructure, intercept or manipulate traffic, or disrupt network availability.

For European organizations, the impact of CVE-2026-2192 can be significant, especially for small and medium enterprises (SMEs) and home office users relying on Tenda AC9 routers. Successful exploitation can lead to full device compromise, allowing attackers to intercept sensitive communications, inject malicious traffic, or pivot into internal networks. This threatens confidentiality by exposing private data, integrity by enabling manipulation of network traffic or device configurations, and availability by causing device crashes or reboots. Given the remote exploitability and high severity, attackers could use this vulnerability to establish persistent footholds or launch further attacks within corporate networks. The absence of widespread public exploits currently reduces immediate risk but does not eliminate it, as threat actors may develop exploits rapidly following disclosure. The vulnerability also raises concerns for critical infrastructure sectors that may use such routers in less monitored environments. Overall, the threat could disrupt business operations, cause data breaches, and undermine trust in network security.

1. Monitor Tenda’s official channels and trusted security advisories for firmware updates addressing CVE-2026-2192 and apply patches promptly once available. 2. Until patches are released, disable remote management interfaces on Tenda AC9 routers to prevent unauthorized external access. 3. Restrict network access to the router’s management interface using firewall rules or network segmentation, limiting access to trusted administrators only. 4. Implement strong authentication mechanisms and change default credentials to reduce the risk of privilege escalation. 5. Employ network intrusion detection systems (NIDS) to monitor for anomalous traffic patterns or attempts to exploit the reboot timer parameters. 6. Conduct regular security audits of network devices and configurations to identify and remediate potential vulnerabilities. 7. Educate users and administrators about the risks of this vulnerability and encourage vigilance against suspicious network activity. 8. Consider replacing vulnerable devices with models from vendors with proven security track records if timely patches are not forthcoming.