Improper XPC caller certificate validation and TOCTOU race condition in macOS PrivilegedHelperTool
Published Jul 1, 2026 · Updated Oct 23, 2026
Original summary
Normalized public record · Updated Oct 23, 2026
Improper XPC caller certificate validation and TOCTOU race condition in macOS PrivilegedHelperTool
Publisher and source text is retained separately from QFinch interpretation.
QFinch assessment
Improper certificate validation and a time-of-check time-of-use (TOCTOU) race condition in the PrivilegedHelperTool XPC service in Cato Client before v.5.13.1 on macOS allows a local authenticated attacker to escalate privileges to root via a self-signed certificate that bypasses the XPC caller verification and a symlink swap during package installation.
Evidence: public source recordsAffected products
| Affected package, product or range | Fix status |
|---|---|
| Consult the referenced vendor advisory for affected versions. | Consult source advisory |
Matching a version is only one part of assessing exposure. QFinch has not assessed your environment on this public page.
Remediation
Apply the vendor-supported fixed release or mitigation, then verify the affected component is no longer reachable.
- Confirm the affected product and reachable code path exist in your environment.
- Apply the vendor-supported patch or mitigation from the primary advisory.
- Rescan the exact deployed revision and retain verification evidence.
Evidence coverage
- SSVC priority
- LOW
- Confidence
- Not available
- Aliases
- None reported
Scores appear only when corresponding evidence exists. Missing data is never interpreted as zero risk.
Sources and record history
Record history
Published Jul 1, 2026 · Last refreshed Oct 23, 2026