CVE-2026-24071 Overview
CVE-2026-24071 affects the privileged helper component of Native Instruments Native Access on macOS. The XPC service exposed by the helper validates connecting clients by retrieving their process identifier (PID) through _xpc_connection_get_pid() and passing it to a hasValidSignature function. This identification method is insecure because PIDs can be reused, allowing a local attacker to impersonate a trusted client. A successful attacker can invoke privileged helper functionality, leading to local privilege escalation on the affected macOS host. The flaw is categorized under [CWE-367] Time-of-Check Time-of-Use (TOCTOU) race condition.
Critical Impact
A local attacker exploiting PID reuse against the Native Access privileged helper can execute operations with elevated privileges, compromising confidentiality, integrity, and availability of the macOS system.
Affected Products
- Native Instruments Native Access (macOS)
- CPE: cpe:2.3:a:native-instruments:native_access:*:*:*:*:*:*:*:*
- Privileged helper XPC service component
Discovery Timeline
- 2026-02-02 - CVE-2026-24071 published to NVD
- 2026-02-11 - Last updated in NVD database
Technical Details for CVE-2026-24071
Vulnerability Analysis
The vulnerability resides in the XPC connection handler of the Native Access privileged helper. When a client process connects, the helper retrieves the client's PID using _xpc_connection_get_pid(arg2) and passes that value to hasValidSignature to verify the caller's code signature. Because PID assignment is not atomic with signature verification, an attacker can exploit the time gap between the check and use of the identifier. This makes the helper trust an attacker-controlled process that briefly inherits or replaces the PID of a legitimately signed binary.
Root Cause
The root cause is the reliance on PID as a stable identity token for XPC clients. PIDs are recycled by the operating system and are not bound to a single process across its lifetime. Apple documents xpc_connection_get_audit_token() as the secure alternative, since audit tokens are kernel-issued and not subject to reuse. The helper's failure to use audit tokens introduces a [CWE-367] TOCTOU condition between signature validation and privileged action execution.
Attack Vector
An attacker with local code execution on the macOS endpoint launches a legitimately signed Native Access binary, then terminates it and rapidly spawns an unsigned attacker-controlled process. If the new process is assigned the same PID before the helper completes its signature check, the helper authorizes the malicious caller. The attacker then sends arbitrary XPC messages to invoke privileged helper functions. Refer to the SEC Consult Security Advisory for the full technical writeup.
No verified proof-of-concept code is published. The vulnerability mechanism is described in prose: a race between PID assignment and signature verification permits an unsigned process to be accepted as a trusted client.
Detection Methods for CVE-2026-24071
Indicators of Compromise
- Rapid process creation and termination cycles involving the Native Access binary on macOS endpoints.
- Unexpected XPC connections to the Native Instruments privileged helper from processes outside the application bundle path.
- Privileged file writes or installer operations initiated by the helper without a corresponding user-driven Native Access workflow.
Detection Strategies
- Monitor launchd and process audit logs for short-lived processes spawning under suspicious parents that target Native Access PIDs.
- Hunt for XPC traffic to the Native Instruments helper service from binaries that are unsigned or signed by non-Native-Instruments identities.
- Apply behavioral identification rules that flag privilege escalation patterns originating from user-level audio software helpers.
Monitoring Recommendations
- Enable macOS Endpoint Security Framework telemetry covering ES_EVENT_TYPE_NOTIFY_EXEC and XPC connection events.
- Track invocations of the privileged helper and correlate them with the parent application's signing identity and bundle path.
- Alert on installer or system modification operations performed by the helper outside expected update windows.
How to Mitigate CVE-2026-24071
Immediate Actions Required
- Update Native Instruments Native Access to the vendor-released fixed version once available.
- Restrict local user privileges on macOS workstations running Native Access to limit attacker opportunity to stage PID reuse races.
- Audit installed privileged helpers under /Library/PrivilegedHelperTools/ and remove unused or outdated entries.
Patch Information
Consult the SEC Consult Security Advisory and Native Instruments support channels for the patched release that replaces PID-based validation with audit-token-based client verification using xpc_connection_get_audit_token().
Workarounds
- Uninstall Native Access on systems where the application is not actively required until a patched build is deployed.
- Remove the vulnerable privileged helper from /Library/PrivilegedHelperTools/ and the associated launchd plist if the application cannot be updated.
- Enforce application allowlisting to prevent unsigned binaries from executing and racing against the helper's signature check.
# Remove the vulnerable privileged helper (run as administrator)
sudo launchctl unload /Library/LaunchDaemons/com.native-instruments.NativeAccess.helper.plist
sudo rm /Library/PrivilegedHelperTools/com.native-instruments.NativeAccess.helper
sudo rm /Library/LaunchDaemons/com.native-instruments.NativeAccess.helper.plist
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
