CVE-2026-43698: Apple macOS Privilege Escalation Flaw

CVE-2026-43698 Overview

CVE-2026-43698 is an argument injection vulnerability [CWE-88] in Apple macOS that allows a local application to escalate privileges to root. Apple addressed the flaw with improved input validation in macOS Sequoia 15.7.8 and macOS Sonoma 14.8.8. Successful exploitation gives an attacker full control over the affected system, including the ability to install persistent malware, disable security tooling, and access protected user data. The vulnerability requires local access and low privileges but no user interaction, making it a practical component of post-compromise attack chains on macOS endpoints.

Critical Impact
A local application can inject arguments into a privileged process and gain root privileges on unpatched macOS Sequoia and Sonoma systems.

Affected Products

Apple macOS Sequoia versions prior to 15.7.8
Apple macOS Sonoma versions prior to 14.8.8
Applications running on affected macOS versions with local execution capability

Discovery Timeline

2026-07-27 - CVE-2026-43698 published to NVD
2026-07-29 - Last updated in NVD database

Technical Details for CVE-2026-43698

Vulnerability Analysis

CVE-2026-43698 is classified as an improper neutralization of argument delimiters in a command [CWE-88], commonly known as argument injection. A component in macOS constructs a command or invocation using attacker-influenced input without adequately validating argument boundaries. A local application can craft input that alters the intended argument structure passed to a privileged process, causing it to interpret attacker-supplied values as its own parameters.

Apple's advisory states the issue was addressed with improved validation. The fix hardens how argument strings are parsed before being handed to the underlying process, closing the injection path.

Root Cause

The root cause is insufficient validation of argument delimiters when a privileged macOS component builds a command line from untrusted input. Special characters or crafted argument sequences are not sanitized, allowing an attacker to append or override arguments the caller did not intend.

Attack Vector

Exploitation requires local access and the ability to execute code with low privileges on the target system. An attacker delivers a malicious application, or leverages an existing foothold, then invokes the vulnerable interface with injected arguments. The privileged process executes with the attacker-controlled parameters and yields root-level code execution. No user interaction is required after the initial application launch.

Apple has not published exploitation code, and no public proof-of-concept is available at this time. Refer to Apple Support Document #128071 and Apple Support Document #128072 for vendor guidance.

Detection Methods for CVE-2026-43698

Indicators of Compromise

Unexpected child processes spawned by system daemons or setuid binaries with unusual argument strings containing delimiters such as --, backticks, or shell metacharacters.
New root-owned files, LaunchDaemons in /Library/LaunchDaemons/, or unsigned binaries in privileged paths shortly after untrusted application execution.
macOS Unified Logs showing privileged tools invoked by non-privileged user sessions with anomalous argv patterns.

Detection Strategies

Monitor process creation telemetry for privileged processes whose parent is a standard user application, especially when command-line arguments include suspicious delimiters or option flags.
Correlate application launches with subsequent privilege transitions to UID 0 that lack a matching authorization prompt.
Baseline normal argument patterns for macOS system utilities and alert on deviations that suggest argument injection.

Monitoring Recommendations

Ingest Endpoint Security Framework (ESF) events for ES_EVENT_TYPE_NOTIFY_EXEC into your detection pipeline and retain full argv arrays for privileged executions.
Track macOS version inventory and flag hosts still running versions earlier than 15.7.8 (Sequoia) or 14.8.8 (Sonoma).
Alert on the appearance of new persistence artifacts under /Library/LaunchDaemons/ or /Library/LaunchAgents/ following execution of newly installed applications.

How to Mitigate CVE-2026-43698

Immediate Actions Required

Update affected endpoints to macOS Sequoia 15.7.8 or macOS Sonoma 14.8.8 as soon as maintenance windows allow.
Restrict installation and execution of unsigned or untrusted applications through Gatekeeper and application allowlisting.
Audit local user accounts on macOS hosts and remove unnecessary interactive access to reduce the pool of potential local attackers.

Patch Information

Apple released fixes in macOS Sequoia 15.7.8 and macOS Sonoma 14.8.8. Patch details are documented in Apple Support Document #128071 and Apple Support Document #128072. Deploy the updates through your MDM solution or via System Settings > General > Software Update on individual hosts.

Workarounds

No vendor-supplied workarounds are available; applying the security updates is the only supported remediation.
As a compensating control, limit local logon rights and enforce least privilege for interactive user accounts until patching is complete.
Enable System Integrity Protection (SIP) and verify it remains active on all managed macOS endpoints.

bash

# Verify installed macOS version and confirm patch level
sw_vers -productVersion

# Trigger available software updates from the command line
sudo softwareupdate --install --all --restart

# Confirm System Integrity Protection status
csrutil status