CVE-2022-26781
📋 TL;DR
This vulnerability allows remote attackers to execute arbitrary code on InHand Networks InRouter302 devices by exploiting improper input validation in libnvram.so and httpd components. Attackers can send specially crafted requests to achieve remote code execution. Organizations using affected InRouter302 devices are at risk.
💻 Affected Systems
- InHand Networks InRouter302
📦 What is this software?
Ir302 Firmware by Inhandnetworks
⚠️ Risk & Real-World Impact
Worst Case
Complete device compromise leading to persistent backdoor installation, network traffic interception, lateral movement to other network segments, and disruption of critical services.
Likely Case
Remote code execution allowing attacker to gain shell access, modify device configuration, install malware, and use device as pivot point for further attacks.
If Mitigated
Limited impact with proper network segmentation, firewall rules blocking unnecessary access to management interfaces, and regular security monitoring.
🎯 Exploit Status
Exploitation requires crafting specific requests but does not require authentication. Technical details are publicly available in the Talos report.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: V3.5.5 or later
Vendor Advisory: https://www.inhandnetworks.com/upload/attachment/202205/10/InHand-PSA-2022-01.pdf
Restart Required: Yes
Instructions:
1. Download latest firmware from InHand Networks support portal. 2. Backup current configuration. 3. Upload and apply firmware update via web interface or CLI. 4. Reboot device. 5. Verify firmware version.
🔧 Temporary Workarounds
Network Access Restriction
linuxRestrict access to device management interfaces to trusted IP addresses only
iptables -A INPUT -p tcp --dport 80 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 443 -s trusted_ip -j ACCEPT
iptables -A INPUT -p tcp --dport 80 -j DROP
iptables -A INPUT -p tcp --dport 443 -j DROP
🧯 If You Can't Patch
- Isolate affected devices in separate VLAN with strict firewall rules
- Disable remote management interfaces if not required
🔍 How to Verify
Check if Vulnerable:
Check firmware version via web interface (System > Status) or CLI command 'cat /etc/version'Check Version:
cat /etc/versionVerify Fix Applied:
Verify firmware version is V3.5.5 or later and test that nvram import functionality rejects malformed input📡 Detection & Monitoring
Log Indicators:
- Multiple failed import attempts
- Unusual nvram variable modifications
- HTTP requests with malformed parameters to management interface
Network Indicators:
- Unusual outbound connections from router
- Traffic to known malicious IPs from router
- Port scanning originating from router
SIEM Query:
source="router_logs" AND (event="import_failed" OR event="nvram_modify" OR http_uri="/cgi-bin/*")