CVE-2025-34051 is a server-side request forgery (SSRF) vulnerability identified in multiple firmware versions of AVTECH DVR devices. The vulnerability resides in the unauthenticated /cgi-bin/nobody/Search.cgi?action=cgi_query endpoint, which allows an attacker to manipulate the 'ip', 'port', and 'queryb64str' parameters to induce the DVR device to send arbitrary HTTP requests. Because this endpoint does not require authentication, an attacker can exploit this flaw remotely without any credentials or user interaction. SSRF vulnerabilities enable attackers to make the vulnerable device act as a proxy to internal or external systems, potentially bypassing network segmentation and firewall rules. This can lead to unauthorized access to sensitive internal services, exposure of confidential data, or interaction with internal management interfaces that are otherwise inaccessible externally. The vulnerability is classified under CWE-918 (SSRF) and CWE-200 (Information Exposure), indicating that exploitation could lead to information disclosure. The CVSS 4.0 base score is 6.9 (medium severity), reflecting that the attack vector is network-based with low attack complexity, no privileges or user interaction required, and limited impact on confidentiality and integrity but some impact on availability and system integrity. The vulnerability affects a wide range of AVTECH DVR firmware versions, indicating a broad attack surface. No known exploits are currently reported in the wild, and no patches have been linked yet, which suggests that organizations using these devices should prioritize mitigation and monitoring. Given the nature of DVR devices in surveillance and security systems, exploitation could also impact physical security monitoring capabilities.

For European organizations, the impact of this SSRF vulnerability can be significant, especially for those relying on AVTECH DVR devices for surveillance and security monitoring. Exploitation could allow attackers to pivot from the DVR device into internal networks, accessing sensitive internal services such as intranet applications, databases, or other IoT devices that are not exposed externally. This could lead to data leakage, unauthorized control over internal systems, or disruption of security monitoring functions. In critical infrastructure sectors such as transportation, energy, or public safety, compromised DVR devices could undermine physical security and safety monitoring, potentially causing operational disruptions or safety hazards. Additionally, the exposure of sensitive data or internal network topology could facilitate further targeted attacks. The medium severity rating suggests that while the vulnerability is serious, it may not directly lead to full system compromise but can be a stepping stone for more complex attacks. European organizations with extensive deployments of AVTECH DVRs, especially in government, healthcare, or industrial environments, should be vigilant. The lack of authentication on the vulnerable endpoint increases the risk of automated scanning and exploitation attempts.

1. Immediate network segmentation: Isolate AVTECH DVR devices on dedicated network segments with strict firewall rules to limit their ability to initiate outbound HTTP requests to sensitive internal systems. 2. Access control: Restrict access to the DVR management interfaces to trusted IP addresses only, preferably via VPN or secure management networks. 3. Monitor network traffic: Implement IDS/IPS rules to detect unusual outbound HTTP requests originating from DVR devices, particularly to internal IP ranges or unexpected external destinations. 4. Firmware updates: Although no patches are currently linked, maintain close communication with AVTECH for firmware updates addressing this vulnerability and apply them promptly once available. 5. Disable or restrict the vulnerable endpoint: If possible, disable the /cgi-bin/nobody/Search.cgi?action=cgi_query endpoint or restrict its functionality via configuration to prevent unauthenticated access. 6. Incident response readiness: Prepare to investigate and respond to potential exploitation attempts by logging access to the vulnerable endpoint and correlating with network traffic anomalies. 7. Vendor engagement: Engage with AVTECH support to confirm affected versions in use and request guidance or interim mitigations. 8. Asset inventory: Maintain an accurate inventory of AVTECH DVR devices and their firmware versions to prioritize remediation efforts.