ClingSTUN Malware Turns Unpatched IoT Devices Into Proxy Nodes

Hytec Inter HWL-2511-SS v1.05 and below was discovered to contain a command injection vulnerability via the component /www/cgi-bin/popen.cgi.

Ivanti Connect Secure (formerly Pulse Connect Secure) and Ivanti Policy Secure appliances contain a command injection flaw (CWE-77) in their web components, triggered when an authenticated administrator sends crafted requests to the appliance. The bug can be chained with the separate authentication bypass CVE-2023-46805, allowing an unauthenticated attacker to achieve the same result. Successful exploitation lets an attacker execute arbitrary commands and code on the appliance, providing a foothold into the networks behind the VPN or network access control gateway. Any organization running these appliances, typically enterprises and government agencies often deployed directly on the internet perimeter, is affected. Exploitation is confirmed in the wild: the flaw was added to CISA's Known Exploited Vulnerabilities catalog on 2024-01-10 with known ransomware use and EPSS assigns a 100% probability of exploitation within 30 days, although no public proof-of-concept is available.

Do: Apply Ivanti's mitigations or patched builds immediately per vendor instructions, addressing the chained authentication bypass CVE-2023-46805 at the same time, and discontinue or restrict use of any appliance for which mitigations are unavailable, especially if it is internet-facing. Because exploitation with ransomware use is known, assume compromise is possible: review appliance web logs for suspicious requests and run Ivanti's integrity-checking guidance to verify appliance images before and after remediation. Where feasible, restrict direct internet exposure of the appliance web interface and monitor for further vendor advisories.

A command injection vulnerability exists in D-Link DAP-1650 devices when handling UPnP SUBSCRIBE messages. An unauthenticated attacker can exploit this vulnerability to gain command execution on the device as root.

EnGenius EnShare Cloud Service 1.4.11 and earlier has an OS command injection flaw (CWE-78) in the usbinteract.cgi script. The path parameter is not properly sanitized, so an unauthenticated remote attacker can inject shell commands that execute as root and fully compromise the device. Affected products are EnGenius ESR300, ESR350, ESR600, ESR900, ESR1200, ESR1750, and EPG5000 firmware that include that EnShare version. Public exploit references exist, and the Shadowserver Foundation reported exploitation evidence on 2024-12-05 UTC. Related reporting describes malware such as ClingSTUN turning unpatched IoT devices into persistent proxy nodes, so internet-exposed units should be treated as potentially compromised.

Do: Install the latest EnGenius firmware for each affected model if it replaces EnShare Cloud Service 1.4.11 or earlier; retire or isolate devices that no longer receive updates. Until patched, block internet access to the web interface and usbinteract.cgi and allow management only from a trusted network. Because exploitation has been observed and commands run as root, check devices for unexpected processes, proxy or backdoor activity, and unauthorized configuration changes.

CVE-2025-67038 is an OS command injection flaw (CWE-78) in the HTTP RPC module of Lantronix EDS5000 series device servers, with firmware 2.1.0.0R3 confirmed affected. When a login attempt fails, the module writes a log entry by building a shell command that directly concatenates the username from the request without any sanitization, so an attacker who sends a crafted username in an authentication request gets their commands appended to it. Because the log-writing command runs as root, an unauthenticated, network-reachable attacker gains full command execution with the highest privileges on the device. Any organization running network-exposed Lantronix EDS5000 device/console servers (EDS5008, EDS5016, EDS5032, and the G526/G527-series variants) is affected. CISA added the flaw to its Known Exploited Vulnerabilities catalog on 2026-06-23 and reports it is being actively exploited; the EPSS score of 19.3% (97th percentile) reflects a high near-term exploitation risk.

Do: Upgrade EDS5000-series firmware to a patched release per Lantronix's guidance, since no fixed version is specified in the available data and 2.1.0.0R3 is confirmed vulnerable; if patching is not yet possible, restrict HTTP access to the device's management interface at the network level. Federal agencies must apply vendor mitigations per CISA BOD 26-04 requirements following the 2026-06-23 KEV listing. Check device logs and configs for signs of compromise, since successful injection yields root-level command execution.

The GoAhead web server on MeiG Smart FORGE_SLT711 devices (firmware MDM9607.LE.1.0-00110-STD.PROD-1) allows unauthenticated OS command injection via the /action/SetRemoteAccessCfg endpoint.