CVE-2026-11516: UTT HiPER 2610G Buffer Overflow in NAT Configuration

Technical summary

The vulnerability stems from unsafe use of strcpy() in the /goform/formNatStaticMap endpoint when processing the NatBinds parameter. This classic buffer overflow (CWE-119, CWE-120) occurs because the web application fails to validate input length before copying user-supplied data into a fixed-size stack or heap buffer. An attacker with valid credentials on the local network can craft a request with an oversized NatBinds value to trigger memory corruption, potentially achieving code execution or information disclosure depending on memory layout and exploitation technique.

Business impact

Organizations deploying UTT HiPER 2610G devices for broadband management face confidentiality, integrity, and availability risks. An authenticated attacker—such as a malicious insider or an adversary who has compromised credentials—can alter NAT configurations, access sensitive network data, or render the device inoperative. For managed service providers and ISPs using these devices at customer premises, this creates support burden and service disruption risk. The public availability of exploit code elevates practical risk beyond theoretical threat modeling.

Affected systems

UTT HiPER 2610G devices running firmware version 3.0.0-171107 and earlier are confirmed vulnerable. Customers should verify their device firmware version via the administrative interface. The vulnerability requires local network access and valid authentication, limiting exposure to trusted internal networks and administrative users. Remote exploitation from the Internet is not possible without prior network or credential compromise.

Exploitability

Exploitation is feasible for authenticated users on the local network. The CVSS 3.1 vector (AV:A/AC:L/PR:L/UI:N/S:U) reflects this: Attack Vector requires Adjacent Network access, Attack Complexity is Low, Privilege escalation requires a valid login, and no user interaction is needed. The public disclosure of exploit code lowers barriers for less skilled adversaries. However, the requirement for valid credentials and local network presence prevents opportunistic mass exploitation from the open Internet.

Remediation

Update UTT HiPER 2610G devices to the latest available firmware version beyond 3.0.0-171107. Verify availability from UTT or your device vendor. Organizations unable to patch immediately should restrict administrative access to the device's web interface, enforce strong authentication, limit local network access to the device via network segmentation, and monitor for suspicious configuration changes. A reboot of the device will clear any exploitation artifacts in memory.

Patch guidance

Obtain the latest firmware release from UTT's official support portal or through your device distributor. Follow the vendor's firmware upgrade procedure carefully to avoid bricking the device. Test in a non-production environment first if feasible. Firmware updates should be applied during a maintenance window to minimize service disruption. If automatic updates are supported, enable them to reduce administrative overhead. Document the upgrade timestamp and version for compliance and incident response records.

Detection guidance

Monitor web server logs on the device (if available) for abnormally long or malformed values in NatBinds parameters sent to /goform/formNatStaticMap. Look for repeated failed login attempts followed by successful authentication and suspicious NAT configuration changes. Intrusion detection systems with payload analysis may flag oversized buffer writes to known vulnerable parameters. Network-based anomaly detection can identify unusual traffic patterns to device management interfaces. Log administrative login events and configuration changes for forensic review.

Why prioritize this

Although CVSS 3.1 rates this as MEDIUM severity (5.5 score), the public exploit code availability, local authentication requirement, and real-world deployment in broadband management justify prioritized patching. Organizations with customer-facing or critical routing infrastructure should treat this as HIGH priority for patching within 30 days. The vulnerability is not listed in CISA's KEV catalog, but that does not diminish risk in managed environments. Prioritize based on device exposure on trusted networks and the criticality of the network services they provide.

Risk score, explained

The CVSS 3.1 score of 5.5 (MEDIUM) reflects the combination of local network requirement (reducing likelihood of widespread remote exploitation) and authenticated access requirement (limiting attacker pool). However, impact is classified as LOW across confidentiality, integrity, and availability because impact scope is limited to the individual device and its local network context rather than cascading across the organization. The score does not account for public exploit availability or the role the device plays in network infrastructure; supplement CVSS with organizational risk context.

Frequently asked questions