CVE-2026-7512 Overview
CVE-2026-7512 is a buffer overflow vulnerability affecting UTT HiPER 1200GW routers up to firmware version 2.5.3-1703. The flaw resides in the strcpy function within the /goform/formUser handler. Attackers can trigger the overflow remotely by sending crafted input to the affected endpoint. A public exploit has been released, increasing the likelihood of opportunistic attacks against exposed devices. The weakness is classified under [CWE-119], improper restriction of operations within the bounds of a memory buffer.
Critical Impact
Remote attackers with low privileges can corrupt memory in the router web management interface, potentially leading to arbitrary code execution or device compromise.
Affected Products
- UTT HiPER 1200GW firmware versions up to and including 2.5.3-1703
- The /goform/formUser endpoint in the device web management interface
- Deployments exposing the router management interface to untrusted networks
Discovery Timeline
- 2026-05-01 - CVE-2026-7512 published to the National Vulnerability Database
- 2026-05-01 - Last updated in NVD database
Technical Details for CVE-2026-7512
Vulnerability Analysis
The vulnerability stems from unsafe use of strcpy inside the /goform/formUser request handler in the HiPER 1200GW web interface. The function copies attacker-controlled input into a fixed-size stack or global buffer without validating the source length. When the supplied data exceeds the destination size, adjacent memory is overwritten.
Memory corruption in this context can produce several outcomes. At minimum, the device crashes and reboots, denying service to network users. With a tailored payload, an attacker can hijack control flow and execute arbitrary code on the embedded Linux operating system that powers the router.
The exploit requires network reachability to the management interface and a low-privilege authenticated session. Because routers commonly use weak default credentials, the privilege requirement offers limited protection. A public proof-of-concept is available through the GitHub PoC Repository and VulDB #360323.
Root Cause
The root cause is the use of the unsafe C library function strcpy without prior length validation of the input copied from the HTTP request. Embedded router firmware frequently relies on legacy string functions, and the formUser handler does not enforce a maximum length before invoking the copy.
Attack Vector
The attack vector is network-based. An attacker sends a crafted HTTP POST request to /goform/formUser with an oversized parameter value. The malformed input overflows the destination buffer during strcpy execution, corrupting saved registers or function pointers. Successful exploitation produces denial of service or arbitrary code execution on the router.
The vulnerability is described in prose because no verified exploitation code is provided. Refer to the GitHub PoC Repository for technical details.
Detection Methods for CVE-2026-7512
Indicators of Compromise
- Unexpected reboots or crashes of the HiPER 1200GW router coinciding with HTTP requests to /goform/formUser
- HTTP POST requests to /goform/formUser containing abnormally long parameter values
- New or modified administrator accounts on the router that were not provisioned by IT
- Outbound traffic from the router management interface to unfamiliar external hosts
Detection Strategies
- Inspect web server and proxy logs for requests targeting /goform/formUser with payload sizes exceeding normal form submission lengths
- Monitor router system logs for segmentation faults, watchdog resets, or process restarts following management traffic
- Deploy network intrusion detection signatures matching oversized parameters in HiPER administrative endpoints
Monitoring Recommendations
- Forward router syslog data to a centralized SIEM or data lake for correlation with network telemetry
- Alert on any access to the router management interface from sources outside an approved administrative subnet
- Track configuration drift on the router to detect unauthorized changes following suspicious requests
How to Mitigate CVE-2026-7512
Immediate Actions Required
- Restrict access to the router management interface to a dedicated administrative VLAN or jump host
- Disable WAN-side access to the web administration interface until a fixed firmware version is available
- Replace default credentials with strong, unique passwords to limit low-privilege exploitation
- Audit existing administrator accounts on affected devices for unauthorized additions
Patch Information
No vendor security advisory or patched firmware release has been published in the available references at the time of writing. Monitor UTT vendor communications and the VulDB #360323 entry for updates. Until a patch is released, rely on network segmentation and access restrictions as compensating controls.
Workarounds
- Place the router management interface behind a firewall rule allowing only trusted administrative IP addresses
- Disable remote management features that expose /goform/formUser over the internet
- Replace end-of-support or unmaintained UTT HiPER 1200GW devices with current, vendor-supported hardware
# Example firewall restriction limiting management access to a trusted subnet
iptables -A INPUT -p tcp --dport 80 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -s 10.0.0.0/24 -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
