CVE-2025-11305 is a remote buffer overflow vulnerability affecting the UTT HiPER 840G device firmware versions up to 3.1.1-190328. The vulnerability resides in the strcpy function call within the /goform/formTaskEdit endpoint, specifically when processing the txtMin2 parameter. Because strcpy does not perform bounds checking, an attacker can supply an overly long input to overflow the buffer, potentially overwriting adjacent memory and enabling arbitrary code execution. The vulnerability is remotely exploitable without requiring authentication or user interaction, making it highly dangerous. The CVSS 4.0 score of 8.7 reflects its high impact on confidentiality, integrity, and availability, with low attack complexity and no privileges needed. The vendor was notified but has not responded or provided patches, and exploit code has been publicly disclosed, increasing the risk of exploitation. Although no active exploitation in the wild has been reported, the availability of exploit code means attackers could weaponize this vulnerability rapidly. The affected product, UTT HiPER 840G, is used in network infrastructure, making this a significant threat to organizations relying on this hardware for critical communications or data transmission.

For European organizations, exploitation of CVE-2025-11305 could lead to complete compromise of affected UTT HiPER 840G devices, resulting in unauthorized access, data breaches, service disruption, or use of the device as a foothold for lateral movement within networks. This is particularly critical for telecommunications providers, government agencies, and critical infrastructure operators who rely on these devices for network management and connectivity. The buffer overflow could allow attackers to execute arbitrary code remotely, potentially leading to data exfiltration, network outages, or deployment of ransomware or other malware. The lack of vendor response and patch availability increases the window of exposure, raising the risk of targeted attacks against European entities. Disruption or compromise of network infrastructure devices can have cascading effects on business continuity and national security.

1. Immediately identify and inventory all UTT HiPER 840G devices running vulnerable firmware versions within your network. 2. Implement network segmentation and isolate these devices from untrusted networks, especially the internet, to reduce exposure. 3. Disable or restrict access to the /goform/formTaskEdit endpoint if possible, using firewall rules or device configuration. 4. Monitor network traffic and device logs for unusual activity or exploitation attempts targeting the txtMin2 parameter or related endpoints. 5. Employ intrusion detection/prevention systems (IDS/IPS) with signatures or heuristics for buffer overflow attempts against this device. 6. Engage with UTT or authorized resellers to obtain firmware updates or patches as soon as they become available. 7. Consider deploying compensating controls such as application-layer gateways or web application firewalls (WAFs) to filter malicious payloads. 8. Prepare incident response plans specifically addressing potential exploitation scenarios involving this vulnerability. 9. Educate network administrators about the vulnerability and recommended defensive measures. 10. Regularly review and update device firmware and configurations to maintain security posture.