AWS Client VPN macOS Vulnerability Allows Root Privilege Escalation (CVE-2025-11462)
October 10th, 2025
Critical
Our Cyber Threat Intelligence Unit has identified a critical local privilege escalation vulnerability in the AWS Client VPN macOS client, tracked as CVE-2025-11462. This vulnerability allows a local, non-administrator user on an affected macOS host to escalate to root privileges by exploiting unsafe log-rotation and symlink handling. A non-privileged user can create a symbolic link from a client log file to a privileged location (e.g., /etc/crontab) and then trigger an internal API that writes attacker-controlled data into that file. When the log rotates, the injected content can be executed with root privileges. The issue affects AWS Client VPN macOS versions 1.3.2 through 5.2.0 and is remediated in version 5.2.1.
Technical Details
CVE ID: CVE-2025-11462.
Attack Type: Local Privilege Escalation via Log Rotation / Symlink Abuse (local file-write cron execution).
Severity: Critical (CVSS 9.3).
Affected Versions: AWS Client VPN macOS 1.3.2 - 5.2.0
Fixed Version: 5.2.1 (and later releases).
Root Cause: Improper validation of the log destination directory during automatic rotation, allowing symbolic links to privileged files.
Exploit Mechanism:
A local user creates a symlink from a client log file to a privileged target (e.g., /etc/crontab).
They invoke the client’s internal logging API to write attacker-controlled data.
When the log rotates, the data is written to the privileged file and executed with root privileges.
Exploit Prerequisites: Local access as a non-administrator on macOS; no network vector required.
Impact
Privilege Escalation to Root: A local attacker can gain total system-level control of the macOS host.
Potential Post-Exploitation Actions: Modify system configuration, install persistence mechanisms, exfiltrate data, or pivot to network targets depending on host placement.
Scope Limitation: Applies only to macOS clients; Windows and Linux editions are not affected.
Operational Risk: Because cron-based execution can be timed and persistent, attackers may use this vulnerability for scheduled root access that evades short-term monitoring.
Detection Method
Symlink Auditing: Inspect AWS Client VPN log directories for symbolic links pointing to privileged paths (e.g., /etc/crontab).
File-Write Correlation: Monitor writes to system configuration or cron files originating from the client process or non-root users during log rotation.
Process Monitoring: Alert on unexpected invocation of the client’s internal logging APIs or unusual log-rotation events.
Cron Integrity Checks: Hunt for recent cron entries added by non-root actors or entries containing unrecognized commands shortly after client activity.
Endpoint Integrity: Correlate new binaries, cron entries, or file changes on macOS hosts with AWS Client VPN events to detect post-exploitation activity.
Indicators of Compromise
There are No Indicators of Compromise (IOCs) for this Advisory.
Recommendations
Immediate Upgrade: Update macOS clients to version 5.2.1 or later (current channel offers 5.3.1). This fully remediates CVE-2025-11462.
Verify Integrity: After upgrading, confirm that the log-rotation directory cannot be symlinked to privileged locations and validate the absence of malicious cron entries.
Harden Local Privileges: Restrict non-admin access and apply macOS hardening controls to reduce local attack surface.
Enhanced Monitoring: Deploy detection signatures outlined above and enable real-time alerts for log-rotation and file-write anomalies.
Incident Response Readiness: Include checks for symlink abuse and malicious cron entries in macOS forensic playbooks.
No Effective Workaround: AWS has not identified any temporary mitigation other than upgrading. Prioritize patching immediately.
Conclusion
CVE-2025-11462 represents a serious local privilege escalation in the AWS Client VPN macOS client, caused by improper handling of log rotation and symbolic links. Exploitation allows a non-privileged user to gain root access and execute arbitrary commands with system permissions. This vulnerability affects macOS client versions 1.3.2 through 5.2.0 and has been fixed in 5.2.1. We urge organizations to treat this vulnerability as a priority, upgrade immediately to version 5.2.1 (or later), and conduct targeted hunts for signs of local symlink abuse and cron-based persistence.