CVE-2021-30300
📋 TL;DR
This vulnerability in Qualcomm Snapdragon chipsets allows denial of service attacks due to improper hex data decoding in SIB2 OTA messages. When processing SRS configuration, the system assigns garbage values, potentially crashing affected devices. This affects numerous Snapdragon-based products across automotive, compute, IoT, wearables, and other sectors.
💻 Affected Systems
- Snapdragon Auto
- Snapdragon Compute
- Snapdragon Connectivity
- Snapdragon Consumer IOT
- Snapdragon Industrial IOT
- Snapdragon Voice & Music
- Snapdragon Wearables
📦 What is this software?
Sd7c Firmware by Qualcomm
⚠️ Risk & Real-World Impact
Worst Case
Complete device crash or reboot, rendering the device unusable until manually restarted or requiring hardware intervention.
Likely Case
Service disruption on affected devices when processing malformed SIB2 OTA messages, causing temporary loss of connectivity or functionality.
If Mitigated
Minimal impact with proper network filtering and updated firmware preventing exploitation attempts.
🎯 Exploit Status
Exploitation requires crafting and sending malformed SIB2 OTA messages to target devices; requires network access to the device's cellular/baseband interface.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Firmware updates released in January 2022 security bulletin
Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/january-2022-bulletin
Restart Required: Yes
Instructions:
1. Check with device manufacturer for firmware updates. 2. Apply Qualcomm-provided firmware patches. 3. Reboot device after update. 4. Verify patch installation through version checks.
🔧 Temporary Workarounds
Network filtering
allImplement network-level filtering to block malformed SIB2 OTA messages
Access control
allRestrict network access to baseband interfaces of affected devices
🧯 If You Can't Patch
- Segment affected devices on isolated networks to limit attack surface
- Implement strict network monitoring for unusual OTA message patterns
🔍 How to Verify
Check if Vulnerable:
Check device firmware version against January 2022 Qualcomm security bulletin; devices with pre-January 2022 firmware are likely vulnerable.Check Version:
Device-specific commands vary by manufacturer; typically 'adb shell getprop ro.build.fingerprint' or manufacturer-specific firmware check utilities.Verify Fix Applied:
Verify firmware version has been updated to include January 2022 security patches from Qualcomm.📡 Detection & Monitoring
Log Indicators:
- Unexpected device reboots
- Baseband/modem crash logs
- SIB2 message processing errors
Network Indicators:
- Unusual OTA message patterns targeting SIB2
- Spike in malformed cellular protocol messages
SIEM Query:
Search for: 'SIB2 processing error' OR 'baseband crash' OR 'modem restart' in device logs