CVE-2025-55099
📋 TL;DR
This vulnerability allows an attacker to trigger an out-of-bounds read in USBX's audio host class implementation when parsing malicious USB descriptors. Systems using Eclipse ThreadX with USBX before version 6.4.3 are affected when processing USB audio devices.
💻 Affected Systems
- Eclipse ThreadX USBX module
📦 What is this software?
⚠️ Risk & Real-World Impact
Worst Case
Information disclosure or denial of service through memory corruption, potentially leading to system instability or crash.
Likely Case
Denial of service causing USB audio functionality disruption or system instability when connecting malicious USB audio devices.
If Mitigated
Limited impact with proper USB device whitelisting and input validation in place.
🎯 Exploit Status
Exploitation requires crafting malicious USB audio device descriptors and physical/network USB access.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: USBX 6.4.3 and later
Vendor Advisory: https://github.com/eclipse-threadx/usbx/security/advisories/GHSA-93mv-fcpr-9488
Restart Required: No
Instructions:
1. Update USBX to version 6.4.3 or later. 2. Rebuild and redeploy ThreadX with updated USBX module. 3. No system restart required for USBX module update.
🔧 Temporary Workarounds
Disable USB audio host class
allDisable USB audio functionality if not required
# In ThreadX configuration, disable UX_HOST_CLASS_AUDIO_ENABLE
USB device whitelisting
allImplement USB device authorization policies
# Configure USB device filtering/whitelisting in system
🧯 If You Can't Patch
- Implement strict USB device access controls and whitelisting
- Disable USB audio functionality in system configuration
🔍 How to Verify
Check if Vulnerable:
Check USBX version in ThreadX build configuration or source codeCheck Version:
# Check USBX version in source: grep -r "UX_VERSION" usbx/common/ux_version.hVerify Fix Applied:
Verify USBX version is 6.4.3 or later in system configuration📡 Detection & Monitoring
Log Indicators:
- USB enumeration failures
- Audio class initialization errors
- System crashes during USB device connection
Network Indicators:
- USB-over-IP connection attempts to audio devices
SIEM Query:
source="system" AND ("USB audio" OR "audio class") AND (error OR fail OR crash)