CVE-2025-12387
📋 TL;DR
A vulnerability in Pix-Link LV-WR21Q routers allows remote attackers to cause a denial of service (DoS) by sending a specially crafted HTTP POST request with a non-existing language parameter. This disrupts the administrator panel functionality while leaving other router services operational. Organizations using affected Pix-Link router models are at risk.
💻 Affected Systems
- Pix-Link LV-WR21Q router
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Persistent administrator panel unavailability requiring physical router reset or configuration restoration, disrupting network management capabilities.
Likely Case
Temporary administrator panel inaccessibility until language settings are manually corrected, causing management disruption.
If Mitigated
Minimal impact if administrator panel access is restricted to internal networks only.
🎯 Exploit Status
Exploitation requires sending a single malformed HTTP POST request; no authentication needed.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: https://www.pix-link.com/lv-wr21q
Restart Required: No
Instructions:
No official patch available. Vendor was notified but has not responded with vulnerability details or fixes.
🔧 Temporary Workarounds
Restrict Administrator Panel Access
allLimit access to the router's administrator panel to trusted internal networks only
Configure firewall rules to block external access to router admin interface (typically port 80/443)
Disable Remote Administration
allTurn off remote administration features if not required
Access router settings → Administration → Remote Management → Disable
🧯 If You Can't Patch
- Implement network segmentation to isolate router management interfaces from untrusted networks
- Monitor for unusual HTTP POST requests to language endpoints and implement rate limiting
🔍 How to Verify
Check if Vulnerable:
Send HTTP POST request to router admin interface with non-existing language parameter and observe if admin panel becomes inaccessibleCheck Version:
Check router web interface → System Status → Firmware VersionVerify Fix Applied:
Test if admin panel remains functional after sending the malformed request📡 Detection & Monitoring
Log Indicators:
- HTTP POST requests with unusual language parameters
- Failed language file requests in web server logs
Network Indicators:
- Multiple HTTP POST requests to language endpoints from single source
- Unusual traffic patterns to router admin interface
SIEM Query:
source="router_logs" AND (http_method="POST" AND uri CONTAINS "lang.js" OR language_parameter="*malformed*")