CVE-2025-62525
📋 TL;DR
Local users on affected OpenWrt systems can read and write arbitrary kernel memory through the ltq-ptm driver ioctls, allowing kernel privilege escalation. This affects OpenWrt installations on Lantiq/Intel/MaxLinear xrx200, danube, and amazon SoCs with DSL in PTM mode. The vulnerability enables sandbox escape from services like ujail.
💻 Affected Systems
- OpenWrt
📦 What is this software?
Openwrt by Openwrt
⚠️ Risk & Real-World Impact
Worst Case
Complete system compromise with root access, persistent backdoor installation, and bypass of all security controls including sandboxing.
Likely Case
Local privilege escalation allowing attackers to gain root privileges and potentially pivot to other systems on the network.
If Mitigated
Limited to local users only, but still enables full system compromise if an attacker gains local access.
🎯 Exploit Status
Requires local access but exploitation appears straightforward through driver ioctls. No public exploit code identified.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: OpenWrt 24.10.4
Vendor Advisory: https://openwrt.org/advisory/2025-10-22-2
Restart Required: Yes
Instructions:
1. Update OpenWrt to version 24.10.4 or later using opkg update && opkg upgrade. 2. Reboot the device to load the patched kernel module. 3. Verify the update was successful.
🔧 Temporary Workarounds
No workarounds available
allThe vendor advisory states there are no workarounds for this vulnerability.
🧯 If You Can't Patch
- Restrict local access to affected devices through strict access controls and network segmentation.
- Monitor for unusual local privilege escalation attempts and kernel module loading activities.
🔍 How to Verify
Check if Vulnerable:
Check OpenWrt version with 'cat /etc/openwrt_release' and verify if version is earlier than 24.10.4. Also check if using affected Lantiq SoC with DSL in PTM mode.Check Version:
cat /etc/openwrt_release | grep VERSIONVerify Fix Applied:
Verify OpenWrt version is 24.10.4 or later with 'cat /etc/openwrt_release'. Check kernel module version with 'modinfo ltq-ptm'.📡 Detection & Monitoring
Log Indicators:
- Unusual ioctl calls to ltq-ptm driver
- Unexpected kernel module loading
- Privilege escalation attempts
Network Indicators:
- None - local exploitation only
SIEM Query:
Process execution where command contains 'ioctl' and target includes 'ltq-ptm' OR kernel module loading of suspicious drivers