CVE-2025-9783
📋 TL;DR
A buffer overflow vulnerability in TOTOLINK A702R routers allows remote attackers to execute arbitrary code by manipulating the submit-url parameter in the formParentControl function. This affects TOTOLINK A702R routers running firmware version 4.0.0-B20211108.1423. The vulnerability is remotely exploitable and has public proof-of-concept code available.
💻 Affected Systems
- TOTOLINK A702R
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Remote code execution leading to complete device compromise, network infiltration, and persistent backdoor installation.
Likely Case
Remote code execution allowing attackers to modify router settings, intercept traffic, or launch attacks against internal networks.
If Mitigated
Denial of service or limited impact if proper network segmentation and access controls are implemented.
🎯 Exploit Status
Public proof-of-concept code exists, making exploitation straightforward for attackers.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: Yes
Instructions:
Check TOTOLINK official website for firmware updates. If available, download latest firmware and apply through web interface.
🔧 Temporary Workarounds
Disable Remote Management
allDisable remote administration features to prevent external exploitation
Network Segmentation
allIsolate router management interface to trusted networks only
🧯 If You Can't Patch
- Replace affected devices with patched or different model routers
- Implement strict firewall rules blocking all external access to router management interface
🔍 How to Verify
Check if Vulnerable:
Check router firmware version in web interface. If version is 4.0.0-B20211108.1423, device is vulnerable.Check Version:
Check router web interface at http://[router-ip]/ or use telnet/ssh if enabledVerify Fix Applied:
Verify firmware version has changed from vulnerable version after update.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to /boafrm/formParentControl with long submit-url parameters
- Router crash/restart logs
Network Indicators:
- Unusual traffic patterns to router management interface
- Exploit payloads in HTTP requests
SIEM Query:
http.method:POST AND http.uri:"/boafrm/formParentControl" AND http.param.submit-url.length > 100🔗 References
- https://github.com/rew1X/CVE/blob/main/TOTOLINK/A702R/formParentControl/formParentControl.md
- https://github.com/rew1X/CVE/blob/main/TOTOLINK/A702R/formParentControl/formParentControl.md#poc
- https://vuldb.com/?ctiid.322085
- https://vuldb.com/?id.322085
- https://vuldb.com/?submit.640991
- https://www.totolink.net/
