CVE-2022-43102 is a critical stack overflow vulnerability identified in the Tenda AC23 router firmware version V16.03.07.45_cn. The vulnerability arises from improper handling of the 'timeZone' parameter within the 'fromSetSysTime' function. Specifically, the stack overflow occurs when the input to this parameter exceeds the expected bounds, allowing an attacker to overwrite the stack memory. This vulnerability is classified under CWE-787 (Out-of-bounds Write), which typically enables attackers to execute arbitrary code, cause denial of service (DoS), or crash the device. The CVSS v3.1 base score of 9.8 reflects the high severity, with an attack vector of network (AV:N), low attack complexity (AC:L), no privileges required (PR:N), and no user interaction needed (UI:N). The impact covers confidentiality, integrity, and availability (C:H/I:H/A:H), meaning an attacker can potentially take full control of the affected device remotely without authentication. Although no known exploits are currently reported in the wild, the nature of the vulnerability and its ease of exploitation make it a significant threat. The affected product is a consumer-grade router, which is commonly deployed in home and small office environments, but can also be found in enterprise branch offices. The lack of a patch link suggests that a fix may not yet be publicly available, increasing the urgency for mitigation.

For European organizations, this vulnerability poses a substantial risk, especially for those relying on Tenda AC23 routers in their network infrastructure. Successful exploitation could lead to complete compromise of the router, enabling attackers to intercept, modify, or redirect network traffic, deploy malware, or establish persistent backdoors. This can result in data breaches, disruption of business operations, and lateral movement within corporate networks. Given the criticality and remote exploitability without authentication, attackers could target vulnerable routers en masse, potentially affecting both private and public sector entities. The impact is particularly severe for organizations with limited network segmentation or those that expose router management interfaces to the internet. Additionally, compromised routers can be leveraged as part of botnets or for launching further attacks, amplifying the threat landscape across Europe.

Immediate mitigation steps include isolating affected Tenda AC23 routers from untrusted networks and disabling remote management interfaces if enabled. Network administrators should monitor network traffic for unusual patterns indicative of exploitation attempts. Since no official patch is currently linked, organizations should contact Tenda support for firmware updates or advisories. As a temporary workaround, restricting access to router management interfaces via firewall rules or VPN-only access can reduce exposure. Implementing network segmentation to separate critical systems from vulnerable devices will limit potential lateral movement. Regularly auditing and updating router firmware, once patches become available, is essential. Additionally, organizations should consider replacing vulnerable devices with models from vendors with stronger security track records if timely patches are not forthcoming. Employing intrusion detection systems (IDS) and endpoint detection and response (EDR) solutions can help detect exploitation attempts and mitigate impact.