CVE-2026-2944 is a remote OS command injection vulnerability found in version 1.01 of the Tosei Online Store Management System ネット店舗管理システム. The vulnerability exists in the /cgi-bin/monitor.php script, specifically within the HTTP POST request handler that processes the DevId parameter. Due to insufficient input validation or sanitization, an attacker can manipulate the DevId argument to inject arbitrary operating system commands. This flaw allows unauthenticated remote attackers to execute commands on the underlying server, potentially gaining control over the system or accessing sensitive data. The vulnerability is exploitable over the network without any authentication or user interaction, increasing its risk profile. Although the vendor was notified early, no response or patch has been issued, and exploit code has been publicly disclosed, raising the likelihood of exploitation. The CVSS 4.0 score of 6.9 reflects a medium severity rating, considering the ease of exploitation and network vector, but limited impact on confidentiality, integrity, and availability. The lack of vendor response and patch availability means organizations must rely on mitigations such as network filtering, input validation, and monitoring. This vulnerability primarily affects deployments of Tosei’s Online Store Management System version 1.01, which is likely used in Japanese and East Asian markets given the product’s language and origin.

The impact of CVE-2026-2944 can be significant for organizations using the affected Tosei Online Store Management System 1.01. Successful exploitation allows remote attackers to execute arbitrary OS commands without authentication, potentially leading to full system compromise. This could result in unauthorized access to sensitive customer and business data, disruption of online store operations, and the deployment of malware or ransomware. The ability to execute commands remotely can also facilitate lateral movement within the network, increasing the scope of compromise. Given the exploit code is publicly available, the risk of automated or opportunistic attacks is heightened. Organizations relying on this software for e-commerce operations may face financial losses, reputational damage, and regulatory consequences if customer data is exposed or service is disrupted. The absence of a vendor patch exacerbates the risk, forcing organizations to implement compensating controls to mitigate potential damage.

1. Immediately restrict network access to the /cgi-bin/monitor.php endpoint by implementing firewall rules or web application firewall (WAF) policies to block unauthorized HTTP POST requests, especially those containing the DevId parameter. 2. Employ input validation and sanitization at the application or proxy level to detect and reject malicious payloads targeting the DevId argument. 3. Monitor web server and application logs for unusual or suspicious POST requests to /cgi-bin/monitor.php, focusing on anomalous DevId parameter values indicative of command injection attempts. 4. Isolate affected systems from critical network segments to limit potential lateral movement if compromise occurs. 5. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics targeting OS command injection patterns. 6. Engage with the vendor or community to track any forthcoming patches or updates and plan for timely application once available. 7. Consider migrating to alternative, actively maintained e-commerce management solutions if patching is not forthcoming. 8. Conduct regular security assessments and penetration testing focused on web application input handling to identify similar vulnerabilities proactively.