CVE-2014-6436 – This vulnerability allows remote attackers to b... (How to Fix)

Q: What is the severity of CVE-2014-6436?

CVE-2014-6436 has a CVSS score of 9.8 (CRITICAL). This vulnerability allows remote attackers to bypass authentication on affected Aztech ADSL routers and execute arbitrary commands with administrator privileges. Attackers can exploit broken session management to gain full control of the device. Users of Aztech DSL5018EN (1T1R), DSL705E, and DSL705EU routers are affected.

📋 TL;DR

This vulnerability allows remote attackers to bypass authentication on affected Aztech ADSL routers and execute arbitrary commands with administrator privileges. Attackers can exploit broken session management to gain full control of the device. Users of Aztech DSL5018EN (1T1R), DSL705E, and DSL705EU routers are affected.

💻 Affected Systems

Products:

Aztech DSL5018EN (1T1R)
Aztech DSL705E
Aztech DSL705EU

Versions: All versions prior to patching

Operating Systems: Embedded firmware

Default Config Vulnerable: ⚠️ Yes

Notes: Affects web management interface on port 80/443. All default configurations are vulnerable.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Complete compromise of router with ability to modify configurations, intercept traffic, install persistent backdoors, or use as pivot point into internal network.

🟠

Likely Case

Router takeover leading to DNS hijacking, traffic interception, credential theft, or denial of service.

🟢

If Mitigated

Limited impact if device is behind firewall with restricted WAN access and proper network segmentation.

🌐 Internet-Facing: HIGH - Directly exposed routers can be exploited remotely without authentication.

🏢 Internal Only: MEDIUM - Internal attackers could exploit if they reach management interface.

🎯 Exploit Status

Public PoC: ⚠️ Yes

Weaponized: CONFIRMED

Unauthenticated Exploit: ⚠️ Yes

Complexity: LOW

Exploit code publicly available since 2014. Attack requires web portal access but no valid credentials.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Unknown

Vendor Advisory: No official vendor advisory found

Restart Required: No

Instructions:

No official patch available. Consider replacing affected devices with supported models.

🔧 Temporary Workarounds

Disable WAN access to management interface

linux

Block external access to router web interface on ports 80 and 443

iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP

Use VPN for management access

all

Only allow router management through VPN connection

🧯 If You Can't Patch

Replace affected routers with supported, patched models
Segment router on isolated network segment with strict firewall rules

🔍 How to Verify

Check if Vulnerable:

Check if you have affected Aztech models. Attempt to access web interface and test session persistence after logout.

Check Version:

Check router web interface or physical label for model number

Verify Fix Applied:

Verify router has been replaced or WAN access to management interface is blocked.

📡 Detection & Monitoring

Log Indicators:

Multiple failed login attempts followed by successful admin access
Unusual commands executed via web interface
Session ID reuse or anomalies

Network Indicators:

External IP accessing router management interface
Unusual outbound connections from router

SIEM Query:

source_ip=external AND dest_port IN (80,443) AND dest_ip=router_ip AND (uri CONTAINS "/cgi-bin/" OR user_agent CONTAINS "exploit")

📊 Metadata

CVE ID: CVE-2014-6436

CVSS v3 Score: 9.8 (CRITICAL)

CVSS Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE: CWE-287

Published: January 12, 2018

Last Updated: November 21, 2024

🔗 References

http://packetstormsecurity.com/files/128254/Aztech-DSL5018EN-DSL705E-DSL705EU-DoS-Broken-Session-Management.html Exploit,Third Party Advisory,VDB Entry
http://www.securityfocus.com/archive/1/533489/100/0/threaded
http://www.securityfocus.com/bid/69811 Third Party Advisory,VDB Entry
http://packetstormsecurity.com/files/128254/Aztech-DSL5018EN-DSL705E-DSL705EU-DoS-Broken-Session-Management.html Exploit,Third Party Advisory,VDB Entry
http://www.securityfocus.com/archive/1/533489/100/0/threaded
http://www.securityfocus.com/bid/69811 Third Party Advisory,VDB Entry

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

If you're affected by CVE-2014-6436, you might also want to check these: