CVE-2025-15461 Overview
CVE-2025-15461 is a buffer overflow vulnerability in the UTT 进取 520W router running firmware version 1.7.7-180627. The flaw resides in the strcpy function call within the /goform/formTaskEdit endpoint. Attackers manipulate the selDateType argument to trigger memory corruption [CWE-119]. The vulnerability is exploitable remotely over the network and requires only low-privileged authentication. A public exploit has been published. The vendor was contacted prior to disclosure but did not respond.
Critical Impact
Remote authenticated attackers can trigger a buffer overflow on affected UTT 520W routers, potentially compromising confidentiality, integrity, and availability of the device.
Affected Products
- UTT 进取 520W firmware version 1.7.7-180627
- UTT 520W hardware revision 3.0
- UTT 520W firmware (all variants matching the affected build)
Discovery Timeline
- 2026-01-05 - CVE-2025-15461 published to NVD
- 2026-01-12 - Last updated in NVD database
Technical Details for CVE-2025-15461
Vulnerability Analysis
The vulnerability stems from unsafe use of the strcpy C library function inside the request handler for /goform/formTaskEdit. The handler copies the attacker-controlled selDateType HTTP parameter into a fixed-size stack buffer without performing length validation. When the supplied value exceeds the destination buffer size, adjacent stack memory is overwritten, including saved return addresses and frame pointers. This classic memory corruption pattern, classified as [CWE-119] (Improper Restriction of Operations within the Bounds of a Memory Buffer), enables an attacker to alter program control flow on the embedded MIPS or ARM processor used in the router. Exploitation requires network reachability to the device's web management interface and a low-privileged authenticated session.
Root Cause
The root cause is the use of strcpy without prior length validation on user-supplied input. The function copies bytes until a null terminator is encountered, ignoring the size of the destination buffer. Embedded router firmware frequently reuses such unsafe string handling in CGI-style form handlers, leaving stack frames exposed to overflow when parameters lack server-side sanitization.
Attack Vector
An authenticated attacker sends a crafted HTTP POST request to the /goform/formTaskEdit endpoint with an oversized selDateType parameter. The malformed payload triggers the stack overflow during request processing. Depending on the firmware's memory protections, the attacker can cause a denial-of-service crash or achieve arbitrary code execution within the web server process context, which typically runs with elevated privileges on the device.
The published proof-of-concept and technical details are available in the GitHub CVE Report and the VulDB #339497 Overview.
Detection Methods for CVE-2025-15461
Indicators of Compromise
- HTTP POST requests to /goform/formTaskEdit containing abnormally long selDateType parameter values.
- Unexpected reboots, web management interface crashes, or httpd process restarts on the UTT 520W device.
- New outbound connections from the router to unfamiliar IP addresses following management interface access.
Detection Strategies
- Inspect network traffic destined for the router's HTTP management interface for parameter lengths exceeding typical form values.
- Apply intrusion detection signatures that match POST bodies to /goform/formTaskEdit containing oversized string parameters.
- Correlate authentication events on the router with subsequent malformed form submissions to identify exploitation attempts.
Monitoring Recommendations
- Log all administrative access to the router web interface and forward logs to a centralized analytics platform.
- Monitor the router's CPU, memory, and reboot counters for anomalies that may indicate exploitation attempts.
- Track lateral movement from the router into the internal network, particularly DNS or routing-table modifications.
How to Mitigate CVE-2025-15461
Immediate Actions Required
- Restrict access to the router's web management interface to trusted internal hosts only and disable WAN-side management.
- Rotate administrator credentials and enforce strong, unique passwords to reduce the risk of credential-based access required for exploitation.
- Place the affected device behind a network firewall that filters unsolicited HTTP traffic to the management port.
Patch Information
At the time of publication, the vendor has not responded to disclosure and no official patch is available for UTT 进取 520W firmware 1.7.7-180627. Organizations should consult the VulDB #339497 Details page for updates on vendor remediation status.
Workarounds
- Disable the /goform/formTaskEdit functionality if not required for operational use, where firmware permits.
- Segment the router onto a dedicated management VLAN with strict access control lists.
- Replace the affected device with a supported router if the vendor does not issue a fix within an acceptable timeframe.
# Example: restrict router management access using upstream firewall rules
iptables -A FORWARD -p tcp -d <router_ip> --dport 80 -s <trusted_mgmt_subnet> -j ACCEPT
iptables -A FORWARD -p tcp -d <router_ip> --dport 80 -j DROP
iptables -A FORWARD -p tcp -d <router_ip> --dport 443 -s <trusted_mgmt_subnet> -j ACCEPT
iptables -A FORWARD -p tcp -d <router_ip> --dport 443 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
