CVE-2022-43260 is a critical stack overflow vulnerability identified in the Tenda AC18 router firmware version V15.03.05.19(6318). The flaw exists in the fromSetSysTime function, specifically related to the handling of the 'time' parameter. A stack overflow occurs when the input data exceeds the buffer size allocated on the stack, which can lead to memory corruption. This vulnerability is classified under CWE-787 (Out-of-bounds Write). The CVSS v3.1 base score is 9.8, indicating a critical severity level. The vector string (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) reveals that the vulnerability is remotely exploitable over the network without any privileges or user interaction required. Successful exploitation could allow an attacker to execute arbitrary code with high privileges, potentially leading to full compromise of the device, including confidentiality, integrity, and availability impacts. The vulnerability affects the router’s system time setting function, which is a common feature in network devices. No patches or mitigations have been officially published at the time of this report, and no known exploits in the wild have been documented yet. Given the nature of the vulnerability and the critical CVSS score, it represents a significant risk to affected devices.

For European organizations, the impact of this vulnerability could be substantial, especially for those relying on Tenda AC18 routers in their network infrastructure. Exploitation could allow attackers to gain control over the router, enabling interception or manipulation of network traffic, disruption of network services, or pivoting to internal networks. This could lead to data breaches, loss of sensitive information, or denial of service. Given that routers are often the first line of defense and critical for network segmentation, compromise could undermine the overall security posture. Additionally, compromised routers could be used as launch points for further attacks within an organization or as part of botnets for large-scale attacks. The lack of required authentication and user interaction increases the risk of automated exploitation attempts. European organizations in sectors such as finance, healthcare, government, and critical infrastructure are particularly at risk due to the sensitive nature of their data and services.

Organizations using Tenda AC18 routers should immediately assess their exposure to this vulnerability. Specific mitigation steps include: 1) Isolate affected devices from untrusted networks or restrict management interfaces to trusted IPs only. 2) Monitor network traffic for unusual activity or signs of exploitation attempts targeting the time setting functionality. 3) Disable remote management features if not required, especially those that allow configuration changes over the network. 4) Implement network segmentation to limit the impact of a compromised router. 5) Regularly back up router configurations and maintain an inventory of affected devices. 6) Engage with Tenda support channels to obtain firmware updates or patches as soon as they become available. 7) Consider deploying intrusion detection/prevention systems (IDS/IPS) with signatures targeting exploitation attempts of this vulnerability. 8) Educate network administrators about the vulnerability and ensure strict access controls to network devices. These measures go beyond generic advice by focusing on network architecture adjustments and proactive monitoring tailored to this specific vulnerability.