CVE-2025-66176
📋 TL;DR
A stack overflow vulnerability in Hikvision Access Control Products allows attackers on the same local network to crash devices by sending specially crafted packets to the search and discovery feature. This affects unpatched Hikvision access control systems using vulnerable firmware versions. The vulnerability requires network access but no authentication.
💻 Affected Systems
- Hikvision Access Control Products
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Complete device malfunction leading to denial of access control services, potentially requiring physical reset or replacement.
Likely Case
Device crashes or becomes unresponsive, disrupting access control operations until manually rebooted.
If Mitigated
Minimal impact with proper network segmentation and patching in place.
🎯 Exploit Status
Exploitation requires crafting specific network packets to trigger the buffer overflow.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check vendor advisory for specific fixed firmware versions
Vendor Advisory: https://www.hikvision.com/en/support/cybersecurity/security-advisory/buffer-overflow-vulnerabilities-in-some-hikvision-products/
Restart Required: Yes
Instructions:
1. Visit Hikvision security advisory page. 2. Identify affected product models. 3. Download latest firmware from Hikvision portal. 4. Apply firmware update via web interface or local console. 5. Reboot device after update.
🔧 Temporary Workarounds
Network Segmentation
allIsolate access control devices on separate VLAN to limit attack surface
Disable Search Feature
allDisable device search and discovery feature if not required
🧯 If You Can't Patch
- Segment access control network from general user networks
- Implement strict firewall rules to limit access to device management ports
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against vendor advisory; devices with vulnerable firmware versions are affected.Check Version:
Check via device web interface: System > Maintenance > Version InformationVerify Fix Applied:
Verify firmware version has been updated to patched version listed in vendor advisory.📡 Detection & Monitoring
Log Indicators:
- Device crash/reboot logs
- Unexpected service restarts
- Memory allocation failures
Network Indicators:
- Unusual UDP traffic to device discovery ports
- Malformed packets to search service
SIEM Query:
source="access_control" AND (event="crash" OR event="reboot") OR dest_port IN (37020, 5353) AND packet_size>threshold