CVE-2020-3686

Q: What is the severity of CVE-2020-3686?

CVE-2020-3686 has a CVSS score of 9.8 (CRITICAL). CVE-2020-3686 is a buffer overflow vulnerability in Qualcomm Snapdragon chipsets that allows remote code execution during music playback. An attacker can exploit this by sending a specially crafted audio bitstream, potentially gaining control of affected devices. This affects numerous Qualcomm Snapdragon platforms across automotive, mobile, IoT, and networking devices.

9.8 CRITICAL

Remote Code Execution Buffer Overflow

📋 TL;DR

CVE-2020-3686 is a buffer overflow vulnerability in Qualcomm Snapdragon chipsets that allows remote code execution during music playback. An attacker can exploit this by sending a specially crafted audio bitstream, potentially gaining control of affected devices. This affects numerous Qualcomm Snapdragon platforms across automotive, mobile, IoT, and networking devices.

💻 Affected Systems

Products:

Snapdragon Auto
Snapdragon Compute
Snapdragon Connectivity
Snapdragon Consumer IOT
Snapdragon Industrial IOT
Snapdragon IoT
Snapdragon Mobile
Snapdragon Voice & Music
Snapdragon Wearables
Snapdragon Wired Infrastructure and Networking

Versions: Specific chipset versions not publicly detailed; refer to Qualcomm December 2020 security bulletin for exact affected versions.

Operating Systems: Android, Linux-based systems using affected Snapdragon chipsets

Default Config Vulnerable: ⚠️ Yes

Notes: Vulnerability exists in the audio processing component of the chipset firmware/software stack.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Remote attacker gains full control of device, executes arbitrary code with kernel privileges, and potentially installs persistent malware or exfiltrates sensitive data.

🟠

Likely Case

Remote code execution leading to device compromise, data theft, or denial of service through device crashes.

🟢

If Mitigated

If patched, no impact. With network segmentation and strict input validation, exploitation risk is significantly reduced.

🌐 Internet-Facing: HIGH - Exploitable via network-delivered malicious audio content without authentication.

🏢 Internal Only: HIGH - Can be exploited through internal network services or user-initiated audio playback.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ⚠️ Yes

Complexity: MEDIUM

Exploitation requires crafting a malicious audio bitstream, but no public exploit code is known. The high CVSS score suggests significant attack potential.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: Refer to Qualcomm December 2020 security bulletin for specific patched versions per product.

Vendor Advisory: https://www.qualcomm.com/company/product-security/bulletins/december-2020-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. 4. Verify patch installation via version checks.

🔧 Temporary Workarounds

Disable vulnerable audio services

all

Temporarily disable or restrict audio playback services that process untrusted content.

# Platform-specific; consult device documentation for service management commands

Network segmentation

all

Isolate affected devices from untrusted networks to prevent remote exploitation.

# Configure firewall rules to restrict inbound/outbound audio-related traffic

🧯 If You Can't Patch

Segment affected devices on isolated network segments with strict access controls.
Implement application allowlisting to prevent execution of unauthorized code.

🔍 How to Verify

Check if Vulnerable:

Check device firmware version against Qualcomm's December 2020 security bulletin or contact device manufacturer.

Check Version:

# Platform-specific; e.g., on Android: 'getprop ro.build.fingerprint' or check Settings > About Phone

Verify Fix Applied:

Confirm firmware version is updated to a version listed as patched in Qualcomm advisory.

📡 Detection & Monitoring

Log Indicators:

Unexpected process crashes in audio services
Memory corruption errors in system logs
Unusual audio file processing attempts

Network Indicators:

Anomalous network traffic to/from audio streaming services
Unexpected audio file downloads

SIEM Query:

Example: 'process:audio* AND (event:crash OR event:memory_violation)'

📊 Metadata

CVE ID: CVE-2020-3686

CVSS v3 Score: 9.8 (CRITICAL)

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CWE: CWE-120

Published: January 21, 2021

Last Updated: November 21, 2024

📋 TL;DR

💻 Affected Systems

📦 What is this software?

Apq8009 by Qualcomm

Apq8009w by Qualcomm

Apq8017 by Qualcomm

Apq8030 by Qualcomm

Apq8037 by Qualcomm

Apq8052 by Qualcomm

Apq8053 by Qualcomm

Apq8056 by Qualcomm

Apq8060a by Qualcomm

Apq8062 by Qualcomm

Apq8064 by Qualcomm

Apq8064au by Qualcomm

Apq8076 by Qualcomm

Apq8084 by Qualcomm

Apq8096au by Qualcomm

Aqt1000 by Qualcomm

Ar6003 by Qualcomm

Ar8031 by Qualcomm

Ar8035 by Qualcomm

Ar8151 by Qualcomm

Csra6620 by Qualcomm

Csra6640 by Qualcomm

Csrb31024 by Qualcomm

Mdm8215 by Qualcomm

Mdm8215m by Qualcomm

Mdm8615m by Qualcomm

Mdm8635m by Qualcomm

Mdm9215 by Qualcomm

Mdm9225 by Qualcomm

Mdm9225m by Qualcomm

Mdm9230 by Qualcomm

Mdm9235m by Qualcomm

Mdm9310 by Qualcomm

Mdm9330 by Qualcomm

Mdm9607 by Qualcomm

Mdm9615 by Qualcomm

Mdm9615m by Qualcomm

Mdm9625 by Qualcomm

Mdm9625m by Qualcomm

Mdm9628 by Qualcomm

Mdm9630 by Qualcomm

Mdm9635m by Qualcomm

Mdm9640 by Qualcomm

Mdm9645 by Qualcomm

Mdm9650 by Qualcomm

Mdm9655 by Qualcomm

Mpq8064 by Qualcomm

Msm8108 by Qualcomm

Msm8208 by Qualcomm

Msm8209 by Qualcomm

Msm8226 by Qualcomm

Msm8227 by Qualcomm

Msm8230 by Qualcomm

Msm8608 by Qualcomm

Msm8610 by Qualcomm

Msm8627 by Qualcomm

Msm8630 by Qualcomm

Msm8909w by Qualcomm

Msm8917 by Qualcomm

Msm8920 by Qualcomm

Msm8930 by Qualcomm

Msm8940 by Qualcomm

Msm8952 by Qualcomm

Msm8953 by Qualcomm

Msm8956 by Qualcomm

Msm8960 by Qualcomm

Msm8960sg by Qualcomm

Msm8962 by Qualcomm

Msm8976 by Qualcomm

Msm8976sg by Qualcomm

Msm8996au by Qualcomm

Pm215 by Qualcomm

Pm3003a by Qualcomm

Pm4125 by Qualcomm

Pm439 by Qualcomm

Pm456 by Qualcomm

Pm6125 by Qualcomm