CVE-2025-9526
📋 TL;DR
A remote stack-based buffer overflow vulnerability exists in the Linksys E1700 router's web interface. Attackers can exploit this by sending specially crafted requests to the /goform/setSysAdm endpoint, potentially allowing remote code execution. This affects Linksys E1700 routers running firmware version 1.0.0.4.003.
💻 Affected Systems
- Linksys E1700
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise allowing attacker to execute arbitrary code, pivot to internal networks, install persistent backdoors, or brick the device.
Likely Case
Remote code execution leading to device takeover, credential theft, or use as a pivot point into internal networks.
If Mitigated
Denial of service or limited information disclosure if exploit fails to achieve full code execution.
🎯 Exploit Status
Proof of concept is publicly available on GitHub. The vulnerability is in an administrative function but may be exploitable without authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
No official patch available. Contact Linksys support for firmware updates. If unavailable, consider replacing the device.
🔧 Temporary Workarounds
Disable Remote Management
allDisable web management interface access from WAN/Internet
Access router admin panel > Administration > Management > Disable 'Remote Management'
Network Segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace affected Linksys E1700 router with a supported model
- Implement strict firewall rules blocking all external access to router management interface (TCP ports 80, 443, 8080)
🔍 How to Verify
Check if Vulnerable:
Check router firmware version via admin panel: Status > Router > Firmware VersionCheck Version:
curl -s http://router-ip/status.cgi | grep FirmwareVerify Fix Applied:
Verify firmware version is no longer 1.0.0.4.003. No official patch exists, so verification requires vendor confirmation.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /goform/setSysAdm
- Large rm_port parameter values in web logs
- Multiple failed authentication attempts followed by setSysAdm requests
Network Indicators:
- Unusual traffic to router management ports from external IPs
- HTTP requests with oversized rm_port parameters
SIEM Query:
source="router_logs" AND (uri_path="/goform/setSysAdm" OR parameter="rm_port")