CVE-2026-52197 Overview
CVE-2026-52197 is a denial of service vulnerability affecting UTT nv518G routers running firmware version nv518GV3v3.2.7-210919-161313. The flaw resides in the gohead/sub_44af70 component and can be triggered remotely without authentication. A remote attacker can send crafted network traffic to the affected component to disrupt device availability. The vulnerability is classified under CWE-400: Uncontrolled Resource Consumption, indicating the affected component fails to properly manage resources when processing attacker-supplied input. Successful exploitation renders the router unavailable, disrupting network connectivity for downstream users.
Critical Impact
Unauthenticated remote attackers can crash the UTT nv518G router via the gohead/sub_44af70 component, causing network outage for all connected clients.
Affected Products
- UTT nv518G router firmware nv518GV3v3.2.7-210919-161313
- gohead/sub_44af70 component
- UTT 518G series devices running the affected firmware build
Discovery Timeline
- 2026-06-30 - CVE-2026-52197 published to NVD
- 2026-07-02 - Last updated in NVD database
Technical Details for CVE-2026-52197
Vulnerability Analysis
The vulnerability affects the gohead/sub_44af70 component of the UTT nv518G router firmware. The gohead process is the embedded web server (GoAhead-derived) handling HTTP-based administrative and management traffic on the device. The function sub_44af70 fails to properly bound or validate resource usage when processing remote requests. An attacker can send network traffic that triggers uncontrolled resource consumption, leading to a denial of service condition on the router.
The issue is remotely reachable, requires no authentication, and requires no user interaction. Impact is limited to availability. Confidentiality and integrity are not affected. Reference material is published in the GitHub CVE Report Repository.
Root Cause
The root cause is uncontrolled resource consumption [CWE-400] in the sub_44af70 routine within the gohead binary. The function does not enforce limits on the resources it allocates or the work it performs while parsing attacker-controlled input. Malformed or oversized input drives the process into a state where CPU or memory resources are exhausted, or the process crashes.
Attack Vector
Attackers reach the vulnerability over the network by sending crafted HTTP requests to the router's management interface serviced by the gohead process. Exposure of the management interface to untrusted networks significantly increases exploitability. The vulnerability does not require credentials or user interaction, and only device availability is impacted. Technical details are documented in the GitHub CVE Report Repository.
Detection Methods for CVE-2026-52197
Indicators of Compromise
- Repeated crashes, reboots, or watchdog-triggered restarts of the gohead process on the router
- Sudden loss of connectivity or management interface unavailability without corresponding administrative action
- Anomalous HTTP requests targeting endpoints served by gohead from external IP ranges
Detection Strategies
- Monitor router uptime and service availability metrics for unexpected process restarts of the embedded web server
- Inspect network flow telemetry for repeated HTTP requests originating from untrusted networks toward the router management port
- Correlate SNMP or syslog events indicating resource exhaustion, high CPU, or memory pressure on affected devices
Monitoring Recommendations
- Forward router syslog output to a central logging platform and alert on gohead restart events
- Track ICMP reachability and management-interface responsiveness for baseline deviations
- Alert on unauthenticated HTTP request bursts to the router management interface
How to Mitigate CVE-2026-52197
Immediate Actions Required
- Restrict access to the router management interface to trusted management VLANs and administrative source IPs
- Disable remote WAN-side administration on affected UTT nv518G devices until a vendor patch is applied
- Inventory all UTT 518G series devices and confirm firmware version against nv518GV3v3.2.7-210919-161313
Patch Information
No vendor patch has been publicly linked in the NVD entry at the time of publication. Administrators should monitor the UTT Model 518G Download Center for updated firmware releases addressing this issue and apply them once available.
Workarounds
- Block inbound traffic to the router management interface at the network perimeter
- Place management interfaces behind a VPN or bastion host reachable only by administrators
- Rate-limit HTTP requests to the router management port to reduce exploitation reliability
# Example ACL restricting management access to a trusted subnet
# Adjust interface names and subnets to match your environment
access-list mgmt-acl permit tcp 10.0.0.0 0.0.0.255 host <router-ip> eq 80
access-list mgmt-acl permit tcp 10.0.0.0 0.0.0.255 host <router-ip> eq 443
access-list mgmt-acl deny tcp any host <router-ip> eq 80
access-list mgmt-acl deny tcp any host <router-ip> eq 443
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
