CVE-2024-41335
📋 TL;DR
This vulnerability in Draytek routers allows attackers to perform timing attacks against insecure strcmp/memcmp implementations, potentially revealing sensitive information like passwords or cryptographic keys. It affects multiple Draytek Vigor router models running outdated firmware versions. Organizations using these vulnerable devices are at risk of information disclosure.
💻 Affected Systems
- Draytek Vigor 165
- Draytek Vigor 166
- Draytek Vigor 2620
- Draytek Vigor LTE200
- Draytek Vigor 2860
- Draytek Vigor 2925
- Draytek Vigor 2862
- Draytek Vigor 2926
- Draytek Vigor 2133
- Draytek Vigor 2762
- Draytek Vigor 2832
- Draytek Vigor 2135
- Draytek Vigor 2765
- Draytek Vigor 2766
- Draytek Vigor 2865
- Draytek Vigor 2866
- Draytek Vigor 2927
- Draytek Vigor 2962
- Draytek Vigor 3910
- Draytek Vigor 3912
⚠️ 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
Attackers could extract administrative credentials, VPN keys, or other sensitive authentication data, leading to full network compromise.
Likely Case
Information disclosure of authentication tokens or configuration data that could facilitate further attacks.
If Mitigated
Limited impact with proper network segmentation and monitoring, though sensitive data exposure risk remains.
🎯 Exploit Status
Timing attacks require sophisticated measurement and statistical analysis. Exploitation depends on the specific authentication or comparison mechanisms using vulnerable functions.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Varies by model - see description for specific fixed versions
Vendor Advisory: http://draytek.com
Restart Required: Yes
Instructions:
1. Identify your Draytek router model. 2. Check current firmware version in web admin interface. 3. Download appropriate firmware update from Draytek support site. 4. Upload firmware via web admin interface. 5. Reboot router after update completes.
🔧 Temporary Workarounds
Network Segmentation
allIsolate vulnerable routers from sensitive network segments to limit potential data exposure
Access Control Restrictions
allLimit administrative access to trusted IP addresses only
🧯 If You Can't Patch
- Replace vulnerable devices with updated models or alternative vendors
- Implement network monitoring for unusual authentication attempts or timing-based attacks
🔍 How to Verify
Check if Vulnerable:
Check firmware version in router web interface and compare against affected versions listed in CVE descriptionCheck Version:
Login to router web interface > System Maintenance > Firmware InformationVerify Fix Applied:
Confirm firmware version matches or exceeds the patched version for your specific model📡 Detection & Monitoring
Log Indicators:
- Multiple failed authentication attempts with timing patterns
- Unusual login patterns from external IPs
Network Indicators:
- Repeated authentication requests to router management interface
- Traffic patterns suggesting timing measurement
SIEM Query:
source="draytek-router" AND (event_type="authentication_failure" OR event_type="login_attempt") | stats count by src_ip, dest_ip, time_interval