CVE-2020-10828 is a critical security vulnerability identified as a stack-based buffer overflow in the cvmd component of Draytek Vigor series routers, specifically the Vigor3900, Vigor2960, and Vigor300B models running firmware versions prior to 1.5.1. This vulnerability allows remote attackers to execute arbitrary code on the affected devices by sending a specially crafted HTTP request. The flaw arises due to improper bounds checking in the handling of HTTP requests, leading to a buffer overflow condition on the stack (CWE-787). Exploitation does not require any authentication or user interaction, and the attack vector is network-based, making it accessible remotely over the internet or internal networks where the device is reachable. The vulnerability has a CVSS v3.1 base score of 9.8, indicating critical severity with high impact on confidentiality, integrity, and availability. Successful exploitation could allow attackers to gain full control of the device, enabling them to intercept, modify, or disrupt network traffic, pivot into internal networks, or deploy further malware. Although no known exploits have been reported in the wild, the ease of exploitation and critical impact make this a significant threat to organizations using these Draytek devices. The lack of available patches at the time of reporting increases the urgency for mitigation.

For European organizations, the impact of CVE-2020-10828 can be severe, especially for those relying on Draytek Vigor3900, Vigor2960, or Vigor300B routers for their network infrastructure. These devices are often deployed in small to medium enterprises, branch offices, and critical network segments. Exploitation could lead to complete compromise of the affected routers, resulting in interception of sensitive data, disruption of business operations, and potential lateral movement within corporate networks. Given the routers' role in managing WAN connectivity and VPNs, attackers could gain persistent access to internal resources, undermining confidentiality and integrity of corporate communications. This could also impact compliance with European data protection regulations such as GDPR, as unauthorized access to personal data could occur. The critical nature of the vulnerability and the remote attack vector increase the risk profile for European entities, particularly those in sectors with high reliance on secure network infrastructure such as finance, healthcare, and government.

Organizations should immediately identify any Draytek Vigor3900, Vigor2960, or Vigor300B devices in their environment and verify firmware versions. If devices are running firmware versions prior to 1.5.1, they should prioritize upgrading to the latest firmware that addresses this vulnerability as soon as it becomes available. In the absence of an official patch, network administrators should implement compensating controls such as restricting management interfaces to trusted IP addresses only, disabling remote HTTP management if not required, or using VPNs for device management to reduce exposure. Network segmentation should be enforced to isolate vulnerable devices from critical internal networks. Additionally, monitoring network traffic for unusual HTTP requests targeting these devices can help detect exploitation attempts. Regular vulnerability scanning and penetration testing should include checks for this vulnerability. Finally, organizations should maintain close communication with Draytek for updates and advisories.