File-access policy bypass via signalable security extension
Published Apr 21, 2026 · Updated Apr 21, 2026
Protection mechanism failure in ClearanceKit before 5.0.6 allows local users with root access to bypass file-access policies. The opfilter Endpoint Security extension accepts SIGSTOP, SIGKILL, and SIGTERM, causing AUTH events to time out and default to allow. Existing root access is required; the policy-blind window permits file exfiltration and execution that active rules would otherwise deny.
Summary
What happened
Protection mechanism failure in ClearanceKit before 5.0.6 allows local users with root access to bypass file-access policies. The opfilter Endpoint Security extension accepts SIGSTOP, SIGKILL, and SIGTERM, causing AUTH events to time out and default to allow. Existing root access is required; the policy-blind window permits file exfiltration and execution that active rules would otherwise deny.
The record
- CVE
- CVE-2026-40604
- Published
- Apr 21, 2026
- Updated
- Apr 21, 2026
- Vendor
- Craig J. Bass
- Product
- ClearanceKit
- Classifications
- CWE-693, T1562.001
- Attack vector
- local
- Privileges
- admin
Timeline
How it unfolded
- Apr 21, 2026CVE publishedPublication date reported by the CVE source.
- Apr 21, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=< 5.0.6
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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