CVE-2022-27642
📋 TL;DR
This vulnerability allows network-adjacent attackers to bypass authentication on NETGEAR R6700v3 routers by exploiting incorrect string matching logic in the httpd service. Attackers can combine this with other vulnerabilities to execute arbitrary code with root privileges. Only users of affected NETGEAR router models with vulnerable firmware versions are impacted.
💻 Affected Systems
- NETGEAR R6700v3
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution as root, allowing complete compromise of the router, network traffic interception, credential theft, and lateral movement to connected devices.
Likely Case
Authentication bypass leading to unauthorized access to router administration interface, configuration changes, and potential privilege escalation through chained exploits.
If Mitigated
Limited impact with proper network segmentation, firewall rules blocking adjacent network access, and intrusion detection monitoring.
🎯 Exploit Status
Authentication bypass is straightforward, but achieving RCE requires chaining with other vulnerabilities. ZDI advisory suggests exploit chain is feasible.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware version 1.0.4.122 or later
Vendor Advisory: https://kb.netgear.com/000064723/Security-Advisory-for-Multiple-Vulnerabilities-on-Multiple-Products-PSV-2021-0327
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates or manually download latest firmware from NETGEAR support site. 4. Upload and install firmware update. 5. Router will reboot automatically.
🔧 Temporary Workarounds
Disable remote administration
allPrevents external access to router admin interface
Network segmentation
allIsolate router management interface to separate VLAN
🧯 If You Can't Patch
- Replace affected router with updated model or different vendor
- Implement strict firewall rules to limit access to router management interface from trusted IPs only
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in admin interface under Advanced > Administration > Firmware UpdateCheck Version:
Not applicable - check via web interfaceVerify Fix Applied:
Confirm firmware version is 1.0.4.122 or later in router admin interface📡 Detection & Monitoring
Log Indicators:
- Failed authentication attempts followed by successful access to protected pages
- Unusual access patterns to router admin interface from unexpected IPs
Network Indicators:
- HTTP requests to router management interface with unusual URI patterns attempting to bypass authentication
SIEM Query:
source="router_logs" AND (event_type="auth_failure" OR event_type="admin_access") | stats count by src_ip🔗 References
- https://kb.netgear.com/000064723/Security-Advisory-for-Multiple-Vulnerabilities-on-Multiple-Products-PSV-2021-0327
- https://www.zerodayinitiative.com/advisories/ZDI-22-518/
- https://kb.netgear.com/000064723/Security-Advisory-for-Multiple-Vulnerabilities-on-Multiple-Products-PSV-2021-0327
- https://www.zerodayinitiative.com/advisories/ZDI-22-518/
