CVE-2020-11306
📋 TL;DR
This CVE describes an integer overflow vulnerability in the RPMB (Replay Protected Memory Block) counter in Qualcomm Snapdragon chipsets. Attackers could exploit this by providing specially crafted data to trigger the overflow, potentially leading to memory corruption. Affected devices include those using Snapdragon Auto, Compute, Connectivity, Consumer IOT, Industrial IOT, Mobile, and Wired Infrastructure and Networking chips.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Consumer IOT
- Snapdragon Industrial IOT
- Snapdragon Mobile
- Snapdragon Wired Infrastructure and Networking
📦 What is this software?
Sd7c Firmware by Qualcomm
⚠️ Risk & Real-World Impact
Worst Case
Successful exploitation could allow an attacker to execute arbitrary code with kernel privileges, potentially leading to complete device compromise, data theft, or persistent backdoor installation.
Likely Case
Most probable impact is denial of service (device crash/reboot) or limited information disclosure due to memory corruption.
If Mitigated
With proper access controls and exploit mitigations, impact may be limited to denial of service or prevented entirely.
🎯 Exploit Status
Exploitation requires local access or ability to send crafted data to RPMB interface; no public exploit code available
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Qualcomm security bulletin for specific chipset firmware versions
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/june-2021-bulletin
Restart Required: Yes
Instructions:
1. Check device manufacturer for firmware updates 2. Apply Qualcomm-provided patches through OEM updates 3. Reboot device after update
🔧 Temporary Workarounds
Restrict RPMB access
linuxLimit access to RPMB interface to trusted processes only
Device-specific configuration required; consult OEM documentation
🧯 If You Can't Patch
- Implement strict access controls to prevent untrusted applications from accessing RPMB functionality
- Monitor for abnormal system behavior or crashes that might indicate exploitation attempts
🔍 How to Verify
Check if Vulnerable:
Check device chipset version and firmware against Qualcomm's patched versions listCheck Version:
Device-specific commands vary by OEM; typically 'getprop ro.build.fingerprint' or similar on AndroidVerify Fix Applied:
Verify firmware version has been updated to patched release from OEM📡 Detection & Monitoring
Log Indicators:
- Kernel panic logs
- Unexpected system reboots
- Memory corruption errors in system logs
Network Indicators:
- Not applicable - local vulnerability
SIEM Query:
Search for: 'kernel panic' OR 'segmentation fault' OR 'unexpected reboot' on affected devices