Craigjbass
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Local privilege escalation in ClearanceKit opfilter system extension allows root-level processes on macOS to completely bypass file-access policy enforcement by suspending or killing the Endpoint Security extension. An attacker with root access can send SIGSTOP to the uk.craigbass.clearancekit.opfilter extension, causing all AUTH events to time out and silently default to allow, effectively disabling all ClearanceKit file-access controls. This represents a critical security control bypass for environments relying on ClearanceKit for file-system access restrictions. Fixed in version 5.0.6. No public exploit identified at time of analysis, though exploitation is straightforward for any attacker who has already achieved root access on the macOS system.
ClearanceKit 5.0.4 and earlier allows local attackers with low-privilege accounts to bypass file-system access controls and read/modify all protected files by spoofing Apple platform binary status. The vulnerability stems from incorrect validation of code signing identifiers - specifically, treating processes with empty Team IDs but non-empty Signing IDs as trusted Apple binaries. Malicious software can exploit this logic flaw to impersonate processes in the global allowlist and gain unauthorized access to sensitive data. CVSS 8.4 reflects high confidentiality and integrity impact in local attack scenarios. EPSS and KEV data not available; no public exploit confirmed at time of analysis, though the GitHub security advisory provides detailed vulnerability disclosure.
Local authenticated attackers can bypass file access policies in ClearanceKit (macOS system extension) versions prior to 4.2.4 by using specific file operation event types (ES_EVENT_TYPE_AUTH_EXCHANGEDATA and ES_EVENT_TYPE_AUTH_CLONE) that were not intercepted by the opfilter enforcement mechanism. This policy bypass allows unauthorized file access, modification, and data exfiltration despite configured access controls. EPSS exploitation probability is minimal (0.01%, 2nd percentile) and no active exploitation or public POC has been identified. Patch available in version 4.2.4 via commit 6181c4a, requiring system extension reactivation.
ClearanceKit 4.1 and earlier for macOS allows local authenticated users to completely bypass configured file access policies via seven unmonitored file operation event types. The opfilter Endpoint Security extension only intercepted ES_EVENT_TYPE_AUTH_OPEN events, enabling processes to perform rename, unlink, and five other file operations without policy enforcement or denial logging. Version 4.2 branch contains the fix via commit a3d1733. No public exploit identified at time of analysis, but exploitation requires only local access with low privileges (CVSS PR:L) and no special complexity.
Policy signing key bypass in ClearanceKit prior to 5.0.10 permits any root process on macOS to forge valid signatures over arbitrary policy database content, granting full control over ClearanceKit's per-process file-system access enforcement plane. The root cause is a silent ACL failure specific to the macOS legacy System Keychain: ECDSA key items persisted via SecItemAdd silently lose their kSecAttrAccess restriction, leaving the signing key unrestricted to any root caller. No public exploit has been identified and no CISA KEV listing exists, but the integrity impact extends beyond the vulnerable component to the entire policy enforcement layer ClearanceKit provides.
ClearanceKit's on-disk SQLite policy store on macOS is vulnerable to a replay attack that allows a high-privileged local attacker to substitute a previously-captured, legitimately-signed policy snapshot, causing the opfilter component to enforce outdated or permissive per-process file-access policies on the next boot. All releases prior to version 5.0.10 are affected, with exploitation gated to specific windows: the opfilter-update period when the Endpoint Security filter is offline, offline-boot scenarios, or decrypted-backup restoration. No public exploit code or CISA KEV listing exists at time of analysis, and EPSS data was not provided in available intelligence.
ClearanceKit for macOS prior to version 5.0.4-beta-1f46165 fails to validate destination paths in dual-path file operations (rename, link, copyfile, exchangedata, clone), allowing authenticated local processes to bypass file-access protection and place or replace files in protected directories. The vulnerability affects all versions before 5.0.4-beta-1f46165 and has been patched; no public exploit code or active exploitation has been identified at the time of analysis.
ClearanceKit on macOS fails to enforce managed and user-defined file-access policies during startup, allowing local processes to bypass intended access controls until GUI interaction triggers policy reloading. The vulnerability affects ClearanceKit versions prior to 4.2.14, where two startup defects create a window in which only a hardcoded baseline rule is enforced, leaving the system vulnerable to privilege escalation and unauthorized file access. This issue is not confirmed actively exploited, but the trivial attack vector (local, no authentication) and high integrity/system impact make it a meaningful risk for systems relying on ClearanceKit for file-access enforcement.
Local privilege escalation in ClearanceKit opfilter system extension allows root-level processes on macOS to completely bypass file-access policy enforcement by suspending or killing the Endpoint Security extension. An attacker with root access can send SIGSTOP to the uk.craigbass.clearancekit.opfilter extension, causing all AUTH events to time out and silently default to allow, effectively disabling all ClearanceKit file-access controls. This represents a critical security control bypass for environments relying on ClearanceKit for file-system access restrictions. Fixed in version 5.0.6. No public exploit identified at time of analysis, though exploitation is straightforward for any attacker who has already achieved root access on the macOS system.
ClearanceKit 5.0.4 and earlier allows local attackers with low-privilege accounts to bypass file-system access controls and read/modify all protected files by spoofing Apple platform binary status. The vulnerability stems from incorrect validation of code signing identifiers - specifically, treating processes with empty Team IDs but non-empty Signing IDs as trusted Apple binaries. Malicious software can exploit this logic flaw to impersonate processes in the global allowlist and gain unauthorized access to sensitive data. CVSS 8.4 reflects high confidentiality and integrity impact in local attack scenarios. EPSS and KEV data not available; no public exploit confirmed at time of analysis, though the GitHub security advisory provides detailed vulnerability disclosure.
Local authenticated attackers can bypass file access policies in ClearanceKit (macOS system extension) versions prior to 4.2.4 by using specific file operation event types (ES_EVENT_TYPE_AUTH_EXCHANGEDATA and ES_EVENT_TYPE_AUTH_CLONE) that were not intercepted by the opfilter enforcement mechanism. This policy bypass allows unauthorized file access, modification, and data exfiltration despite configured access controls. EPSS exploitation probability is minimal (0.01%, 2nd percentile) and no active exploitation or public POC has been identified. Patch available in version 4.2.4 via commit 6181c4a, requiring system extension reactivation.
ClearanceKit 4.1 and earlier for macOS allows local authenticated users to completely bypass configured file access policies via seven unmonitored file operation event types. The opfilter Endpoint Security extension only intercepted ES_EVENT_TYPE_AUTH_OPEN events, enabling processes to perform rename, unlink, and five other file operations without policy enforcement or denial logging. Version 4.2 branch contains the fix via commit a3d1733. No public exploit identified at time of analysis, but exploitation requires only local access with low privileges (CVSS PR:L) and no special complexity.
Policy signing key bypass in ClearanceKit prior to 5.0.10 permits any root process on macOS to forge valid signatures over arbitrary policy database content, granting full control over ClearanceKit's per-process file-system access enforcement plane. The root cause is a silent ACL failure specific to the macOS legacy System Keychain: ECDSA key items persisted via SecItemAdd silently lose their kSecAttrAccess restriction, leaving the signing key unrestricted to any root caller. No public exploit has been identified and no CISA KEV listing exists, but the integrity impact extends beyond the vulnerable component to the entire policy enforcement layer ClearanceKit provides.
ClearanceKit's on-disk SQLite policy store on macOS is vulnerable to a replay attack that allows a high-privileged local attacker to substitute a previously-captured, legitimately-signed policy snapshot, causing the opfilter component to enforce outdated or permissive per-process file-access policies on the next boot. All releases prior to version 5.0.10 are affected, with exploitation gated to specific windows: the opfilter-update period when the Endpoint Security filter is offline, offline-boot scenarios, or decrypted-backup restoration. No public exploit code or CISA KEV listing exists at time of analysis, and EPSS data was not provided in available intelligence.
ClearanceKit for macOS prior to version 5.0.4-beta-1f46165 fails to validate destination paths in dual-path file operations (rename, link, copyfile, exchangedata, clone), allowing authenticated local processes to bypass file-access protection and place or replace files in protected directories. The vulnerability affects all versions before 5.0.4-beta-1f46165 and has been patched; no public exploit code or active exploitation has been identified at the time of analysis.
ClearanceKit on macOS fails to enforce managed and user-defined file-access policies during startup, allowing local processes to bypass intended access controls until GUI interaction triggers policy reloading. The vulnerability affects ClearanceKit versions prior to 4.2.14, where two startup defects create a window in which only a hardcoded baseline rule is enforced, leaving the system vulnerable to privilege escalation and unauthorized file access. This issue is not confirmed actively exploited, but the trivial attack vector (local, no authentication) and high integrity/system impact make it a meaningful risk for systems relying on ClearanceKit for file-access enforcement.