CVE-2020-9877 – CVE-2020-9877 is an out-of-bounds read vulnerab... (How to Fix)

Q: What is the severity of CVE-2020-9877?

CVE-2020-9877 has a CVSS score of 7.8 (HIGH). CVE-2020-9877 is an out-of-bounds read vulnerability in Apple's image processing that could allow arbitrary code execution when processing malicious images. This affects multiple Apple operating systems and applications. Attackers could exploit this to gain control of affected devices.

📋 TL;DR

CVE-2020-9877 is an out-of-bounds read vulnerability in Apple's image processing that could allow arbitrary code execution when processing malicious images. This affects multiple Apple operating systems and applications. Attackers could exploit this to gain control of affected devices.

💻 Affected Systems

Products:

iOS
iPadOS
macOS
tvOS
watchOS
iTunes for Windows
iCloud for Windows

Versions: Versions before iOS 13.6, iPadOS 13.6, macOS Catalina 10.15.6, tvOS 13.4.8, watchOS 6.2.8, iTunes 12.10.8, iCloud for Windows 11.3/7.20

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

Default Config Vulnerable: ⚠️ Yes

Notes: All default configurations are vulnerable. The vulnerability is in core image processing libraries.

📦 What is this software?

⚠️ Risk & Real-World Impact

🔴

Worst Case

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

🟠

Likely Case

Application crash or limited code execution in the context of the vulnerable image processing component.

🟢

If Mitigated

No impact if patched or if malicious images are blocked before processing.

🌐 Internet-Facing: MEDIUM - Requires user interaction to open malicious image, but common in web/messaging contexts.

🏢 Internal Only: LOW - Requires user interaction with malicious content, less likely in controlled environments.

🎯 Exploit Status

Public PoC: ✅ No

Weaponized: UNKNOWN

Unauthenticated Exploit: ✅ No

Complexity: MEDIUM

Exploitation requires user interaction to process malicious image. No public exploit code is known.

🛠️ Fix & Mitigation

✅ Official Fix

Patch Version: iOS 13.6, iPadOS 13.6, macOS Catalina 10.15.6, tvOS 13.4.8, watchOS 6.2.8, iTunes 12.10.8, iCloud for Windows 11.3/7.20

Vendor Advisory: https://support.apple.com/kb/HT211288

Restart Required: Yes

Instructions:

1. Go to Settings > General > Software Update on iOS/iPadOS. 2. Go to System Preferences > Software Update on macOS. 3. For Windows applications, update via Apple Software Update or download from Apple website. 4. Restart device after installation.

🔧 Temporary Workarounds

Block suspicious image files

all

Use email/web gateways to block suspicious image attachments and downloads.

Disable automatic image processing

all

Configure applications to not automatically open or process image files from untrusted sources.

🧯 If You Can't Patch

Implement network segmentation to isolate vulnerable devices
Deploy application whitelisting to prevent unauthorized code execution

🔍 How to Verify

Check if Vulnerable:

Check current OS/application version against affected versions list.

Check Version:

iOS/iPadOS: Settings > General > About > Version; macOS: About This Mac > Overview; Windows: Help > About in iTunes/iCloud

Verify Fix Applied:

Verify installed version matches or exceeds patched versions listed in fix_official.

📡 Detection & Monitoring

Log Indicators:

Application crashes in image processing components
Unusual process spawning from image viewers/editors

Network Indicators:

Downloads of suspicious image files from untrusted sources

SIEM Query:

Image: (process_name="*image*" OR process_name="*photo*") AND (event_type="crash" OR parent_process="*explorer*")

📊 Metadata

CVE ID: CVE-2020-9877

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: October 22, 2020

Last Updated: November 21, 2024

🔗 References

https://support.apple.com/kb/HT211288 Vendor Advisory
https://support.apple.com/kb/HT211289 Vendor Advisory
https://support.apple.com/kb/HT211290 Vendor Advisory
https://support.apple.com/kb/HT211291 Vendor Advisory
https://support.apple.com/kb/HT211293 Vendor Advisory
https://support.apple.com/kb/HT211294 Vendor Advisory
https://support.apple.com/kb/HT211295 Vendor Advisory
https://support.apple.com/kb/HT211288 Vendor Advisory
https://support.apple.com/kb/HT211289 Vendor Advisory
https://support.apple.com/kb/HT211290 Vendor Advisory
https://support.apple.com/kb/HT211291 Vendor Advisory
https://support.apple.com/kb/HT211293 Vendor Advisory
https://support.apple.com/kb/HT211294 Vendor Advisory
https://support.apple.com/kb/HT211295 Vendor Advisory

📤 Share & Export

📄 Export Markdown 📋 Export JSON

🔗 Related Vulnerabilities

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