CVE-2020-9837
📋 TL;DR
CVE-2020-9837 is an out-of-bounds read vulnerability in Apple operating systems that allows a remote attacker to leak memory, potentially exposing sensitive information. It affects users of iOS, iPadOS, macOS, and tvOS who have not updated to the patched versions.
💻 Affected Systems
- iOS
- iPadOS
- macOS
- tvOS
📦 What is this software?
Ipados by Apple
Tvos by Apple
⚠️ Risk & Real-World Impact
Worst Case
An attacker could exploit this to read arbitrary memory contents, leading to information disclosure such as passwords, encryption keys, or other sensitive data, which might facilitate further attacks like privilege escalation or system compromise.
Likely Case
In most scenarios, exploitation results in memory leakage that could reveal limited information, potentially aiding in reconnaissance or enabling other vulnerabilities, but direct remote code execution is less probable.
If Mitigated
With proper controls like network segmentation and up-to-date patches, the impact is minimal, reducing the risk to information disclosure without significant operational disruption.
🎯 Exploit Status
Exploitation likely requires crafting malicious inputs to trigger the out-of-bounds read, but no public proof-of-concept has been disclosed, making real-world attacks less common.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: iOS 13.5, iPadOS 13.5, macOS Catalina 10.15.5, tvOS 13.4.5
Vendor Advisory: https://support.apple.com/HT211168
Restart Required: Yes
Instructions:
1. Open Settings on iOS/iPadOS/tvOS or System Preferences on macOS. 2. Go to General > Software Update. 3. Download and install the available update. 4. Restart the device after installation completes.
🔧 Temporary Workarounds
Network Segmentation
allLimit network access to affected devices to reduce exposure to remote attacks.
🧯 If You Can't Patch
- Isolate affected systems from untrusted networks to minimize attack surface.
- Monitor for unusual memory access patterns or crashes that could indicate exploitation attempts.
🔍 How to Verify
Check if Vulnerable:
Check the current OS version: on iOS/iPadOS/tvOS, go to Settings > General > About > Version; on macOS, go to Apple menu > About This Mac > Overview. If the version is earlier than the patched ones listed, the system is vulnerable.Check Version:
On macOS, run 'sw_vers' in terminal; on iOS/iPadOS/tvOS, use the Settings method as no direct command is available.Verify Fix Applied:
After updating, verify the OS version matches or exceeds iOS 13.5, iPadOS 13.5, macOS Catalina 10.15.5, or tvOS 13.4.5 using the same steps as checking vulnerability.📡 Detection & Monitoring
Log Indicators:
- Look for system crashes or abnormal memory access logs in system logs, such as kernel panics or application errors related to memory bounds.
Network Indicators:
- Monitor for unusual inbound network traffic to affected devices, especially from unknown sources attempting to exploit memory vulnerabilities.
SIEM Query:
Example: 'event_type:crash AND os_version:<13.5' for iOS/iPadOS/tvOS, or 'event_type:kernel_panic AND os_version:<10.15.5' for macOS.