Description Preview
The Zyxel P-2602HW-D1A router’s firmware 3.40(AJZ.1) maintains authentication state based on the client’s IP address. An attacker can bypass login requirements by initiating a session from a source IP address that has previously authenticated within the last 5 minutes, effectively hijacking the user’s session without needing valid credentials. This is a remote, IP-based authentication–state vulnerability that could enable unauthorized configuration changes or access to restricted features on affected devices.
Overview
This CVE describes an authentication mechanism flaw in the Zyxel P-2602HW-D1A router where the device tracks authenticated sessions by IP address. As a result, an attacker can spoof or reuse a source IP that recently authenticated to gain access without re-authenticating, provided the session occurs within a short window (five minutes). The vulnerability stems from simplistic session state handling rather than robust per-session authentication tokens, making it possible for remote attackers to bypass authentication on affected devices with the referenced firmware version.
Remediation
- Check for and apply the latest firmware update from Zyxel for the P-2602HW-D1A and upgrade to a version that fixes the IP-based session management vulnerability.
- If no patch is available, implement mitigations to reduce exposure:
- Disable or restrict WAN/remote management access to the router’s configuration interface.
- Restrict administration access to trusted LAN IPs and use strong, unique admin credentials.
- Enable HTTPS/SSL for the admin interface and disable insecure management protocols (if possible).
- Place the router behind a firewall with strict inbound rules and monitor login attempts for anomalies.
- Regularly monitor device logs for unusual authentication events and consider replacing the device if no vendor fix is available.
- After any update or mitigation, reconfigure the device securely and back up the configuration.
References
- The Router Hacking Challenge is Over! — http://www.securityfocus.com/archive/1/489009/100/0/threaded
- http://www.gnucitizen.org/projects/router-hacking-challenge/
- zyxel-ipaddress-authentication-bypass(41112) — https://exchange.xforce.ibmcloud.com/vulnerabilities/41112
Industry ExposureMost to leastThis section illustrates the prevalence of a specific Common Vulnerabilities and Exposures (CVE) across various industries based on customer reports. The ranking displays industries from the most to least affected by this particular vulnerability, offering valuable insight into where this CVE has been most frequently observed. This information can help organizations within these sectors prioritize their security efforts, understand their relative risk exposure compared to their peers, and focus remediation strategies where they are most needed. By understanding the industry-specific impact, organizations can make more informed decisions regarding patching, resource allocation, and overall risk management related to this CVE.
This section illustrates the prevalence of a specific Common Vulnerabilities and Exposures (CVE) across various industries based on customer reports. The ranking displays industries from the most to least affected by this particular vulnerability, offering valuable insight into where this CVE has been most frequently observed. This information can help organizations within these sectors prioritize their security efforts, understand their relative risk exposure compared to their peers, and focus remediation strategies where they are most needed. By understanding the industry-specific impact, organizations can make more informed decisions regarding patching, resource allocation, and overall risk management related to this CVE.
- Accommodation & Food ServicesAccommodation & Food Services: Low
- Administrative, Support, Waste Management & Remediation ServicesAdministrative, Support, Waste Management & Remediation Services: Low
- Agriculture, Forestry Fishing & HuntingAgriculture, Forestry Fishing & Hunting: Low
- Arts, Entertainment & RecreationArts, Entertainment & Recreation: Low
- ConstructionConstruction: Low
- Educational ServicesEducational Services: Low
- Finance and InsuranceFinance and Insurance: Low
- Health Care & Social AssistanceHealth Care & Social Assistance: Low
- InformationInformation: Low
- Management of Companies & EnterprisesManagement of Companies & Enterprises: Low
- ManufacturingManufacturing: Low
- MiningMining: Low
- Other Services (except Public Administration)Other Services (except Public Administration): Low
- Professional, Scientific, & Technical ServicesProfessional, Scientific, & Technical Services: Low
- Public AdministrationPublic Administration: Low
- Real Estate Rental & LeasingReal Estate Rental & Leasing: Low
- Retail TradeRetail Trade: Low
- Transportation & WarehousingTransportation & Warehousing: Low
- UtilitiesUtilities: Low
- Wholesale TradeWholesale Trade: Low

