CVE-2026-9632: UTT HiPER 1250GW Buffer Overflow Flaw

CVE-2026-9632 Overview

CVE-2026-9632 is a stack-based buffer overflow vulnerability in the UTT HiPER 1250GW router, affecting firmware versions up to 3.2.7-210907-180535. The flaw resides in the strcpy function call within the /goform/formGroupConfig endpoint of the Web Management Interface. Attackers can manipulate the Profile argument to overflow the stack buffer and corrupt adjacent memory. The vulnerability is remotely exploitable over the network, and a public exploit has been released. The weakness is classified under CWE-119, covering improper restriction of operations within the bounds of a memory buffer.

Critical Impact
Remote attackers with low privileges can trigger memory corruption in the router's web management interface, potentially leading to arbitrary code execution or denial of service on the affected device.

Affected Products

UTT HiPER 1250GW router
Firmware versions up to and including 3.2.7-210907-180535
Web Management Interface component (/goform/formGroupConfig)

Discovery Timeline

2026-05-27 - CVE-2026-9632 published to NVD
2026-05-27 - Last updated in NVD database

Technical Details for CVE-2026-9632

Vulnerability Analysis

The vulnerability stems from an unsafe call to strcpy inside the handler for /goform/formGroupConfig. The handler copies the user-supplied Profile parameter into a fixed-size stack buffer without validating the input length. When an attacker submits a Profile value longer than the destination buffer, the copy operation writes past the buffer boundary and overwrites adjacent stack memory, including saved return addresses.

The Web Management Interface is the primary administrative surface of the router. An authenticated attacker with low privileges can issue a crafted HTTP request to trigger the overflow remotely. Successful exploitation can corrupt control flow, crash the device, or execute attacker-controlled code in the context of the web server process.

Root Cause

The root cause is the use of the unbounded strcpy function on attacker-controlled input. The function does not check destination buffer size before copying, and the firmware does not perform prior length validation on the Profile field. This pattern is a textbook [CWE-119] memory boundary violation.

Attack Vector

The attack vector is network-based. An attacker requires authenticated access to the Web Management Interface but no user interaction. The exploit involves sending an HTTP POST request to /goform/formGroupConfig with an overlong Profile parameter. A working proof-of-concept has been published in the GitHub CVE Documentation, and details are tracked in VulDB #365741.

No verified exploit code is reproduced here. Refer to the linked references for technical details of the request structure and overflow offsets.

Detection Methods for CVE-2026-9632

Indicators of Compromise

Unexpected reboots or crashes of UTT HiPER 1250GW devices following inbound HTTP traffic to the management interface
HTTP POST requests to /goform/formGroupConfig containing abnormally long Profile parameter values
Authenticated sessions to the router web interface from unfamiliar source IP addresses
Loss of management plane availability while data plane remains functional

Detection Strategies

Inspect web server and router access logs for POST requests targeting /goform/formGroupConfig with payload sizes exceeding normal configuration values
Deploy network intrusion detection signatures that flag overlong Profile parameters in HTTP requests destined for the router management VLAN
Correlate router crash events with preceding HTTP traffic to identify potential exploitation attempts

Monitoring Recommendations

Restrict and log all access to the router Web Management Interface, including failed authentication attempts
Forward router syslog and crash dumps to a centralized logging platform for retention and correlation
Monitor for unexpected configuration changes to group profiles or firewall rules on affected devices

How to Mitigate CVE-2026-9632

Immediate Actions Required

Block access to the Web Management Interface from untrusted networks and the WAN side of the router
Restrict management access to a dedicated administrative VLAN or jump host
Rotate administrative credentials on all UTT HiPER 1250GW devices to reduce risk from credential reuse
Audit router configurations for unauthorized changes to group profiles or access control rules

Patch Information

At the time of publication, no vendor patch has been referenced in the available advisory data. Administrators should monitor the VulDB entry and UTT vendor channels for firmware updates addressing the strcpy call in /goform/formGroupConfig. Until a fix is available, network-level controls remain the primary defense.

Workarounds

Disable remote administration over WAN interfaces and limit HTTP/HTTPS management to trusted internal hosts
Place affected routers behind a network firewall that filters direct access to /goform/ endpoints from non-administrative sources
Consider replacing affected devices in high-risk deployments until a vendor patch is released

bash

# Example: restrict access to the router management interface using iptables on an upstream gateway
iptables -A FORWARD -d <router_ip> -p tcp --dport 80 -s <admin_subnet> -j ACCEPT
iptables -A FORWARD -d <router_ip> -p tcp --dport 80 -j DROP
iptables -A FORWARD -d <router_ip> -p tcp --dport 443 -s <admin_subnet> -j ACCEPT
iptables -A FORWARD -d <router_ip> -p tcp --dport 443 -j DROP