CVE-2020-9791 – CVE-2020-9791 is an out-of-bounds read vulnerab... (How to Fix)

Q: What is the severity of CVE-2020-9791?

CVE-2020-9791 has a CVSS score of 7.8 (HIGH). CVE-2020-9791 is an out-of-bounds read vulnerability in Apple's audio file processing that could allow arbitrary code execution when processing malicious audio files. This affects users of iOS, iPadOS, macOS, tvOS, and watchOS who open untrusted audio files. Attackers could potentially gain control of affected devices.

📋 TL;DR

CVE-2020-9791 is an out-of-bounds read vulnerability in Apple's audio file processing that could allow arbitrary code execution when processing malicious audio files. This affects users of iOS, iPadOS, macOS, tvOS, and watchOS who open untrusted audio files. Attackers could potentially gain control of affected devices.

💻 Affected Systems

Products:

iOS
iPadOS
macOS
tvOS
watchOS

Versions: Versions before iOS 13.5, iPadOS 13.5, macOS Catalina 10.15.5, tvOS 13.4.5, watchOS 6.2.5

Operating Systems: iOS, iPadOS, macOS, tvOS, watchOS

Default Config Vulnerable: ⚠️ Yes

Notes: All default configurations are vulnerable. Requires processing of malicious audio files.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

Full device compromise with attacker gaining root/system privileges and persistent access

🟠

Likely Case

Application crash or limited code execution within the audio processing context

🟢

If Mitigated

No impact if patched or if malicious files are blocked

🌐 Internet-Facing: MEDIUM - Requires user interaction to open malicious file, but could be delivered via web or email

🏢 Internal Only: LOW - Requires local file access or user interaction with malicious content

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Requires user to open malicious audio file. No public exploit code available.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: iOS 13.5, iPadOS 13.5, macOS Catalina 10.15.5, tvOS 13.4.5, watchOS 6.2.5

Vendor Advisory: https://support.apple.com/HT211168

Restart Required: Yes

Instructions:

1. Go to Settings > General > Software Update on iOS/iPadOS/watchOS. 2. Go to System Preferences > Software Update on macOS. 3. Install the latest available update. 4. Restart device after installation.

🔧 Temporary Workarounds

Block untrusted audio files

all

Prevent users from opening audio files from untrusted sources

Disable automatic file processing

all

Configure systems to not automatically process audio files

🧯 If You Can't Patch

Implement application whitelisting to block unauthorized audio processing applications
Use network filtering to block download of audio files from untrusted sources

🔍 How to Verify

Check if Vulnerable:

Check device version against affected versions list

Check Version:

iOS/iPadOS: Settings > General > About > Version; macOS: Apple menu > About This Mac; tvOS: Settings > General > About; watchOS: Settings > General > About

Verify Fix Applied:

Verify device is running patched version: iOS 13.5+, iPadOS 13.5+, macOS 10.15.5+, tvOS 13.4.5+, watchOS 6.2.5+

📡 Detection & Monitoring

Log Indicators:

Application crashes in audio processing components
Unexpected file processing activity

Network Indicators:

Downloads of audio files from suspicious sources

SIEM Query:

source="apple_system_logs" AND (process="coreaudiod" OR process="audio" OR event="crash")

📊 Metadata

CVE ID: CVE-2020-9791

CVSS v3 Score: 7.8 (HIGH)

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

CWE: CWE-125

Published: June 9, 2020

Last Updated: November 21, 2024

🔗 References

https://support.apple.com/HT211168 Release Notes,Vendor Advisory
https://support.apple.com/HT211170 Release Notes,Vendor Advisory
https://support.apple.com/HT211171 Release Notes,Vendor Advisory
https://support.apple.com/HT211175 Release Notes,Vendor Advisory
https://support.apple.com/HT211168 Release Notes,Vendor Advisory
https://support.apple.com/HT211170 Release Notes,Vendor Advisory
https://support.apple.com/HT211171 Release Notes,Vendor Advisory
https://support.apple.com/HT211175 Release Notes,Vendor Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

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