Vulnerabilities Zyxel Patches Critical Vulnerability in Many Device Models The issue impacts the UPnP function of multiple device models and could be exploited for remote code execution. By Ionut Arghire | February 26, 2026 (7:09 AM ET) Flipboard Reddit Whatsapp Whatsapp Email Networking provider Zyxel this week released patches for multiple vulnerabilities across dozens of device models, including a critical flaw leading to remote code execution. The critical-severity bug, tracked as CVE-2025-13942 (CVSS score of 9.8), is described as a command injection issue affecting the UPnP feature of 18 routers, ONTs, and wireless extenders. An attacker could exploit the flaw via crafted UPnP SOAP requests to execute OS commands on a vulnerable device, Zyxel explains in its advisory . “It is important to note that WAN access is disabled by default on these devices, and the attack can be carried out remotely only if both WAN access and the vulnerable UPnP function have been enabled,” the company notes. The networking provider’s fresh round of security updates also resolves CVE-2025-13943 and CVE-2026-1459, two high-severity command injection defects. Impacting the log file download function and the TR-369 certificate download CGI program of specific router firmware versions, the two vulnerabilities could allow an authenticated attacker to execute OS commands. Advertisement. Scroll to continue reading. Additionally, Zyxel released fixes for four null pointer dereference vulnerabilities that could be exploited by attackers with administrator privileges to cause denial-of-service (DoS) conditions. Affecting various endpoints of the vulnerable products, these flaws can be exploited via crafted HTTP requests if WAN access is enabled and the attacker possesses compromised user credentials. Zyxel has published a list of impacted devices, saying that firmware updates are available for all of them. The company makes no mention of any of these vulnerabilities being exploited in the wild, but threat actors are known to have targeted Zyxel bugs in attacks. Related: Cisco Patches Catalyst SD-WAN Zero-Day Exploited by Highly Sophisticated Hackers Related: Zyxel Firewall Vulnerability Again in Attacker Crosshairs Related: Zyxel Issues ‘No Patch’ Warning for Exploited Zero-Days Related: Nvidia, Zoom, Zyxel Patch High-Severity Vulnerabilities Written By Ionut Arghire Ionut Arghire is an international correspondent for SecurityWeek. More from Ionut Arghire CarGurus Data Breach Impacts Over 12 Million Users Astelia Raises $35 Million for Exposure Management Ad Tech Company Optimizely Targeted in Cyberattack ‘Arkanix Stealer’ Malware Disappears Shortly After Debut New ‘Sandworm_Mode’ Supply Chain Attack Hits NPM GitHub Issues Abused in Copilot Attack Leading to Repository Takeover Anonymous Fénix Members Arrested in Spain Ukrainian Gets 5 Years in US Prison for Aiding North Korean IT Fraud Latest News US Sanctions Russian Exploit Broker Operation Zero Trend Micro Patches Critical Apex One Vulnerabilities Cisco Patches Catalyst SD-WAN Zero-Day Exploited by Highly Sophisticated Hackers The Blast Radius Problem: Stolen Credentials Are Weaponizing Agentic AI Google Disrupts Chinese Hackers Targeting Telecoms, Governments SolarWinds Patches Four Critical Serv-U Vulnerabilities Medical Device Maker UFP Technologies Hit by Cyberattack Ex-US Defense Contractor Executive Jailed for Selling Exploits to Russia Trending Daily Briefing Newsletter Subscribe to the SecurityWeek Email Briefing to stay informed on the latest threats, trends, and technology, along with insightful columns from industry experts. Webinar: Identity Under Attack: Why Every Business Must Respond Now February 11, 2026 Attendees will walk away with guidance for how to build robust identity defenses, unify them under a consistent security model, and ensure business operations move quickly without compromise. Register Virtual Event: Ransomware Resilience & Recovery 2026 Summit February 25, 2026 SecurityWeek’s 2026 Ransomware Summit will discuss a roadmap for defending the enterprise, from mitigating root causes to mastering recovery, giving security teams the critical insights needed to navigate and neutralize today’s ransomware extortion threats. Submit People on the Move Menlo Security has named Bill Robbins as Chief Executive Officer. Axonius has named a new CMO and a new AFS leader. Wealth management platform Envestnet announced the appointment of Rich Friedberg as CISO. More People On The Move Expert Insights How to Eliminate the Technical Debt of Insecure AI-Assisted Software Development Developers must view AI as a collaborator to be closely monitored, rather than an autonomous entity to be unleashed. Without such a mindset, crippling tech debt is inevitable. (Matias Madou) Security in the Dark: Recognizing the Signs of Hidden Information Security failures don’t always start with attackers, sometimes they start with missing truth. (Joshua Goldfarb) Living off the AI: The Next Evolution of Attacker Tradecraft Living off the AI isn’t a hypothetical but a natural continuation of the tradecraft we’ve all been defending against, now mapped onto assistants, agents, and MCP. (Etay Maor) Why We Can’t Let AI Take the Wheel of Cyber Defense The fastest way to squander the promise of AI is to mistake automation for assurance, and novelty for resilience. (Steve Durbin) The Upside Down is Real: What Stranger Things Teaches Us About Modern Cybersecurity To all those who are fighting the good fight in the world of cyber, keep collaborating to ensure our world never succumbs to the chaos of the Upside Down. (Nadir Izrael) Flipboard Reddit Whatsapp Whatsapp Email