CVE-2022-28391 is a high-severity vulnerability affecting BusyBox versions up to 1.35.0. BusyBox is a widely used software suite that provides several Unix utilities in a single executable, commonly deployed in embedded systems and lightweight Linux distributions. This vulnerability arises when the netstat utility, part of BusyBox, is used to display DNS PTR record values on a VT (virtual terminal) compatible terminal. An attacker can craft malicious DNS PTR records containing specially designed payloads that, when processed and displayed by netstat, allow remote code execution (RCE) on the victim system. Alternatively, the attacker can manipulate the terminal's colors, indicating control over terminal output sequences. The root cause relates to improper handling of terminal escape sequences embedded within DNS PTR record data, leading to command injection or terminal control sequence injection (CWE-88). The CVSS v3.1 score of 8.8 reflects the vulnerability's critical impact: it requires no privileges (PR:N), no user authentication (UI:R, meaning user interaction is required but minimal), and can be exploited remotely over the network (AV:N). The vulnerability affects confidentiality, integrity, and availability, as arbitrary code execution can lead to full system compromise. No patches or vendor-specific product details are provided in the source information, but the vulnerability is publicly disclosed and documented. No known exploits in the wild have been reported yet, but the ease of exploitation and high impact make it a significant threat, especially for systems relying on BusyBox netstat for network diagnostics or monitoring.

For European organizations, the impact of CVE-2022-28391 can be substantial, particularly for those using embedded Linux devices, IoT infrastructure, or lightweight Linux distributions that include BusyBox. Critical infrastructure sectors such as telecommunications, manufacturing, energy, and transportation often deploy embedded systems that rely on BusyBox utilities. Exploitation could lead to unauthorized remote code execution, enabling attackers to gain control over affected devices, disrupt services, exfiltrate sensitive data, or pivot within internal networks. Since the vulnerability can be triggered remotely without authentication, attackers could leverage malicious DNS PTR records to compromise devices that perform network diagnostics or monitoring. This is especially concerning for organizations with automated network management tools that parse DNS PTR records using netstat. The ability to alter terminal colors also suggests potential for social engineering or obfuscation of malicious activity. Given the widespread use of BusyBox in embedded and IoT devices, the threat extends beyond traditional IT systems to operational technology (OT) environments, increasing the risk of physical process disruptions. The absence of known exploits in the wild currently provides a window for proactive mitigation, but the high CVSS score indicates urgent attention is warranted.

To mitigate CVE-2022-28391 effectively, European organizations should: 1) Identify and inventory all devices and systems running BusyBox, especially those with versions up to 1.35.0. 2) Apply patches or updates from BusyBox maintainers as soon as they become available; if no official patch exists, consider upgrading to a BusyBox version beyond 1.35.0 where the vulnerability is fixed. 3) Restrict or monitor the use of netstat commands that display DNS PTR records on VT-compatible terminals, especially in automated scripts or network monitoring tools. 4) Implement network-level filtering to block or sanitize suspicious DNS responses, particularly those containing unusual or malformed PTR records, using DNS security extensions (DNSSEC) or DNS filtering solutions. 5) Employ strict network segmentation to isolate embedded and IoT devices from critical infrastructure and sensitive networks, limiting the blast radius of potential exploitation. 6) Enhance logging and monitoring for unusual terminal activity or unexpected netstat invocations, enabling early detection of exploitation attempts. 7) Educate system administrators and security teams about the risks of terminal escape sequence injection and the importance of validating external data before display. These targeted steps go beyond generic advice by focusing on the unique characteristics of this vulnerability and the environments where BusyBox is prevalent.