CVE-2025-22941 is a critical command injection vulnerability identified in the web interface of the Adtran 411 Optical Network Terminal (ONT) device, specifically version L80.00.0011.M2. This vulnerability allows an unauthenticated remote attacker to execute arbitrary commands on the device with root-level privileges. The root cause is improper input validation in the web interface, leading to command injection (CWE-77). Exploiting this flaw requires no authentication and no user interaction, making it highly accessible to attackers. The vulnerability has a CVSS v3.1 base score of 9.8, reflecting its critical severity with network attack vector, low attack complexity, no privileges required, and no user interaction needed. Successful exploitation compromises confidentiality, integrity, and availability of the device, enabling attackers to fully control the ONT, potentially pivot into the internal network, intercept or manipulate traffic, and disrupt services. Although no public exploits are currently known, the severity and ease of exploitation make it a significant threat. The lack of available patches at the time of publication increases the urgency for mitigation and monitoring. Adtran 411 ONTs are commonly deployed by ISPs and enterprises for fiber broadband access, making this vulnerability particularly impactful for network infrastructure relying on these devices.

For European organizations, this vulnerability poses a substantial risk to network infrastructure, especially for ISPs, telecommunications providers, and enterprises using Adtran 411 ONTs for fiber access. Compromise of these devices can lead to full network takeover, interception of sensitive communications, disruption of internet services, and lateral movement into corporate or critical infrastructure networks. Given the critical nature of telecommunications infrastructure in Europe, exploitation could affect service availability and data confidentiality on a large scale. This threat could also impact regulatory compliance, such as GDPR, due to potential data breaches. The ability to escalate privileges to root without authentication amplifies the risk of widespread exploitation and persistent backdoors in affected networks.

1. Immediate network segmentation: Isolate Adtran 411 ONTs from critical internal networks to limit lateral movement if compromised. 2. Restrict access to the web interface: Limit management interface exposure by allowing access only from trusted IP addresses or via VPN. 3. Monitor network traffic and device logs for unusual command execution patterns or unauthorized access attempts. 4. Deploy intrusion detection/prevention systems (IDS/IPS) with signatures targeting command injection attempts against Adtran devices. 5. Engage with Adtran support or vendors for patches or firmware updates; apply them promptly once available. 6. If patches are unavailable, consider temporary device replacement or alternative solutions to reduce exposure. 7. Conduct regular vulnerability assessments and penetration tests focusing on network devices to detect similar issues. 8. Implement strict input validation and web interface hardening policies in network device management practices. 9. Educate network administrators about this vulnerability to ensure rapid detection and response.