CVE-2026-20695: Apple macOS Information Disclosure Flaw

CVE-2026-20695 Overview

CVE-2026-20695 is a memory information disclosure vulnerability affecting multiple versions of Apple macOS. The vulnerability exists due to improper memory management that allows a local application to determine kernel memory layout. This type of information leakage can be leveraged by attackers to bypass security mechanisms such as Kernel Address Space Layout Randomization (KASLR), potentially facilitating more sophisticated kernel-level attacks.

Critical Impact

A malicious application running on an affected macOS system can determine kernel memory layout, potentially bypassing KASLR protections and enabling subsequent privilege escalation or kernel exploitation attacks.

Affected Products

• macOS Sequoia versions prior to 15.7.5
• macOS Sonoma versions prior to 14.8.5
• macOS Tahoe versions prior to 26.4

Discovery Timeline

• 2026-03-25 - CVE-2026-20695 published to NVD
• 2026-03-26 - Last updated in NVD database

Technical Details for CVE-2026-20695

Vulnerability Analysis

This vulnerability stems from an information disclosure flaw in macOS kernel memory management. When exploited, a locally running application can infer or directly access information about the kernel's memory layout. This undermines critical security boundaries between user-space applications and the kernel, as knowledge of kernel memory addresses allows attackers to craft targeted exploits that bypass Address Space Layout Randomization (ASLR) protections implemented at the kernel level.

The vulnerability requires local access to execute, meaning an attacker would need the ability to run code on the target system. While this limits the initial attack surface, it presents a significant risk in scenarios where users may inadvertently install malicious applications or in multi-user environments where privilege separation is critical.

Root Cause

The root cause is improper memory management within macOS kernel operations. Sensitive kernel memory address information is inadvertently exposed to user-space applications, likely through system calls, memory mappings, or information leakage in kernel data structures accessible from user mode. Apple addressed this by implementing improved memory management practices that properly isolate kernel address information from user-space processes.

Attack Vector

The attack vector is local, requiring an attacker to first gain code execution on the target macOS system. This could be achieved through:

• A malicious application installed by the user
• Exploitation of another vulnerability to gain initial code execution
• Social engineering to convince users to run untrusted code

Once executing on the system, the malicious application can query or infer kernel memory layout information. This data can then be used to:

1. Defeat KASLR protections by determining actual kernel addresses
2. Craft precise kernel exploits targeting specific memory locations
3. Enable privilege escalation through kernel memory corruption attacks

The vulnerability manifests through memory management operations that fail to properly sanitize or restrict kernel address information from user-space visibility. Technical details regarding the specific API or system component involved can be found in Apple's security advisories.

Detection Methods for CVE-2026-20695

Indicators of Compromise

• Unusual application behavior involving repeated queries to kernel or system information APIs
• Applications attempting to probe memory regions or system internals without legitimate purpose
• Presence of unknown or recently installed applications with suspicious memory access patterns

Detection Strategies

• Monitor for applications making excessive calls to system information or memory-related APIs
• Deploy endpoint detection solutions capable of identifying kernel information probing behavior
• Implement application allowlisting to prevent unauthorized applications from executing
• Review system logs for unusual application activity targeting system internals

Monitoring Recommendations

• Enable comprehensive logging of application execution and system call activity
• Configure security solutions to alert on potential KASLR bypass attempts
• Regularly audit installed applications and remove any untrusted software
• Monitor for behavioral indicators associated with privilege escalation attempts

How to Mitigate CVE-2026-20695

Immediate Actions Required

• Update macOS Sequoia to version 15.7.5 or later
• Update macOS Sonoma to version 14.8.5 or later
• Update macOS Tahoe to version 26.4 or later
• Review installed applications and remove any untrusted or unnecessary software
• Enable Gatekeeper and only allow applications from the App Store or identified developers

Patch Information

Apple has released security updates addressing this vulnerability across multiple macOS versions. Administrators and users should apply the appropriate update for their macOS version immediately:

• macOS Sequoia 15.7.5: Apple Security Update #126794
• macOS Sonoma 14.8.5: Apple Security Update #126795
• macOS Tahoe 26.4: Apple Security Update #126796

The fix implements improved memory management to prevent kernel memory layout information from being accessible to user-space applications.

Workarounds

• Restrict application installation to trusted sources and enable Gatekeeper strict mode
• Implement application control policies to prevent unauthorized application execution
• Limit user privileges and avoid running daily operations with administrator accounts
• Deploy endpoint protection solutions capable of detecting kernel exploitation attempts
• Isolate sensitive systems until patches can be applied

# Enable Gatekeeper strict mode (App Store only)
sudo spctl --master-enable
sudo spctl --enable --label "Mac App Store"

# Verify Gatekeeper status
spctl --status

# Check for available macOS updates
softwareupdate --list