CVE-2021-29065
📋 TL;DR
CVE-2021-29065 is an authentication bypass vulnerability in NETGEAR RBR850 routers that allows attackers to gain unauthorized access to the device's administrative interface without valid credentials. This affects all NETGEAR RBR850 devices running firmware versions before 3.2.10.11. Attackers can exploit this to take full control of the router.
💻 Affected Systems
- NETGEAR RBR850
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete compromise of the router allowing attackers to intercept all network traffic, modify DNS settings, install malware, and pivot to internal network devices.
Likely Case
Unauthorized access to router configuration, enabling attackers to change network settings, monitor traffic, or disable security features.
If Mitigated
Limited impact if router is behind firewall with restricted WAN access and strong network segmentation.
🎯 Exploit Status
Authentication bypass typically requires minimal technical skill. Public exploit details exist in security advisories.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.2.10.11 and later
Vendor Advisory: https://kb.netgear.com/000063006/Security-Advisory-for-Authentication-Bypass-on-RBR850-PSV-2020-0029
Restart Required: Yes
Instructions:
1. Log into router admin interface. 2. Navigate to Advanced > Administration > Firmware Update. 3. Check for updates and install version 3.2.10.11 or later. 4. Router will automatically restart after update.
🔧 Temporary Workarounds
Disable Remote Management
allPrevents external attackers from accessing the admin interface over the internet
Network Segmentation
allPlace router on isolated management network with restricted access
🧯 If You Can't Patch
- Replace affected device with patched model or different vendor
- Implement strict network access controls to limit who can reach the router's admin interface
🔍 How to Verify
Check if Vulnerable:
Check current firmware version in router admin interface under Advanced > Administration > Firmware UpdateCheck Version:
No CLI command - check via web interface at http://routerlogin.net or router IPVerify Fix Applied:
Confirm firmware version is 3.2.10.11 or later in the same location📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to admin interface
- Successful logins from unexpected IP addresses
- Configuration changes without proper authentication
Network Indicators:
- HTTP requests to router admin interface from external IPs
- Unusual traffic patterns to router management ports
SIEM Query:
source="router" AND (event="login_success" OR event="config_change") AND user="unknown" OR src_ip NOT IN [allowed_management_ips]