{"Id":"c2feb6de-46fe-44ab-93c2-634ea6ab83a2","Tags":["mbamchameleon.sys"],"Verified":"TRUE","Author":"Xusheng Li, Michael Haag","Created":"2026-09-18","MitreID":"T1562.001","Category":"vulnerable driver","Commands":{"Command":"","Description":"Malwarebytes' mbamchameleon.sys 3.2.0.456 exposes process termination to verified, registered client processes. The reported Bring Your Own Trusted Caller technique abuses administrator-level control of a genuine signed Malwarebytes client: the driver's on-disk image verification does not attest to the integrity of code executing inside that client. Static analysis confirms client verification and registration through IOCTL 0x222008 and a current-process client-state gate before IOCTL 0x222024 reaches ZwTerminateProcess for a supplied process identifier. An unrelated unsigned process does not meet those checks. The driver must be loaded and the caller must execute inside a verified, registered client. This record is limited to the reviewed sample and does not assert that all current product versions are affected.","Usecase":"Abuse a trusted client to terminate processes and impair endpoint defenses.","Privileges":"Administrator-level control of a genuine verified and registered client process.","OperatingSystem":"Windows"},"Resources":["https://github.com/magicsword-io/LOLDrivers/issues/435","https://xusheng.dev/posts/byotc/main/"],"Acknowledgement":{"Person":"Xusheng Li","Handle":"@xusheng6"},"Detection":[],"KnownVulnerableSamples":[{"Filename":"mbamchameleon.sys","SHA256":"d86b9b20788b6bff70a1a4c4111b2ea33b9ec705cc6b8fe869362fc3899820a3","MD5":"1258a8e1beab105aa96c93aa34dd9ef8","SHA1":"a435a462a0976135e2257b46e52b576fabac3d34","Imphash":"9f4ab3bb8a1adfb8e5bebea149d4e25c","Authentihash":{"MD5":"8dc1927fadf434f857e62d0d1e130696","SHA1":"51d336ef7563a3377a5f8d9b8917b7dfbe115350","SHA256":"69e1de5800cd3fc5b7f37c5babcb0888b7fc152557251d507f735bcf7f697430"},"RichPEHeaderHash":{"MD5":"123afc72f66274a9f7193f5c648fb797","SHA1":"088bc4b9de1ef6cd7671be545432203201c59566","SHA256":"730a081f62964d2c8b76a7e7bc795d76e06d3f2e7f0fa574727ee9a6363380f0"},"Sections":{".text":{"Entropy":6.379318533402795,"Virtual Size":"0x29458"},"NONPAGE":{"Entropy":5.023341731835175,"Virtual Size":"0xa1"},".rdata":{"Entropy":4.780050130444651,"Virtual Size":"0x4e7c"},".data":{"Entropy":5.525904839377678,"Virtual Size":"0x1a30"},".pdata":{"Entropy":5.400811282471703,"Virtual Size":"0x13bc"},"PAGE":{"Entropy":6.335345441469745,"Virtual Size":"0x39f4"},"INIT":{"Entropy":5.664100151511142,"Virtual Size":"0x203a"},".rsrc":{"Entropy":3.2610462586940194,"Virtual Size":"0x3b8"},".reloc":{"Entropy":5.007758370304079,"Virtual Size":"0xcc"}},"MagicHeader":"50 45 0 0","CreationTimestamp":"2025-01-23 19:43:38","Description":"Malwarebytes Chameleon","Company":"Malwarebytes","InternalName":"mbamchameleon.sys","OriginalFilename":"mbamchameleon.sys","FileVersion":"3.2.0.456","Product":"Malwarebytes Chameleon","ProductVersion":"3.2.0.456","Copyright":"(C) Malwarebytes. All rights reserved.","MachineType":"AMD64","Imports":["fwpkclnt.sys","ntoskrnl.exe","cng.sys","FLTMGR.SYS"],"ExportedFunctions":"","ImportedFunctions":["FwpmEngineClose0","FwpmTransactionBegin0","FwpmTransactionCommit0","FwpmTransactionAbort0","FwpmSubLayerAdd0","FwpmCalloutAdd0","FwpmFilterAdd0","FwpmFilterDeleteById0","FwpsCalloutRegister1","FwpsCalloutUnregisterById0","FwpmEngineOpen0","IoGetStackLimits","KeExpandKernelStackAndCallout","RtlQueryRegistryValues","RtlStringFromGUID","VerSetConditionMask","RtlGetVersion","RtlVerifyVersionInfo","KeInitializeEvent","KeInitializeGuardedMutex","MmGetSystemRoutineAddress","IoCreateSymbolicLink","IoDeleteDevice","IoDeleteSymbolicLink","IoRegisterShutdownNotification","IoUnregisterShutdownNotification","IoWMIRegistrationControl","IoRegisterPlugPlayNotification","IoUnregisterPlugPlayNotificationEx","ObGetFilterVersion","ZwOpenKey","ZwQueryValueKey","IoRegisterDriverReinitialization","KeAcquireGuardedMutex","KeReleaseGuardedMutex","ObRegisterCallbacks","ObUnRegisterCallbacks","DbgPrint","MmProbeAndLockPages","MmUnlockPages","MmMapLockedPagesSpecifyCache","IoAllocateMdl","IoFreeMdl","ObReferenceObjectByPointer","MmIsAddressValid","PsSetCreateProcessNotifyRoutineEx","PsSetCreateThreadNotifyRoutine","PsRemoveCreateThreadNotifyRoutine","PsSetLoadImageNotifyRoutine","PsRemoveLoadImageNotifyRoutine","ZwOpenProcess","KeStackAttachProcess","KeUnstackDetachProcess","ZwOpenProcessTokenEx","ZwQueryInformationToken","IoFileObjectType","RtlAppendUnicodeStringToString","RtlAppendUnicodeToString","ExGetPreviousMode","CmUnRegisterCallback","CmRegisterCallbackEx","FsRtlDoesNameContainWildCards","RtlCompareMemory","IoBuildDeviceIoControlRequest","IofCallDriver","IoGetDeviceObjectPointer","IoGetRelatedDeviceObject","IoGetDeviceProperty","IoOpenDeviceRegistryKey","IoGetDevicePropertyData","ObReferenceObjectByHandle","FsRtlIsNameInExpression","ZwOpenFile","ZwSetValueKey","IoGetDeviceAttachmentBaseRef","swprintf_s","rand","srand","KeClearEvent","KeSetEvent","IoCreateNotificationEvent","RtlCompareUnicodeString","KeQueryTimeIncrement","MmUnmapLockedPages","IofCompleteRequest","ZwCreateFile","ZwSetInformationFile","ZwCreateKey","ZwDeleteKey","ZwDeleteValueKey","ZwEnumerateKey","ZwQueryKey","ZwTerminateProcess","ZwDeleteFile","ZwQueryDirectoryFile","ZwQuerySystemInformation","ZwOpenThread","toupper","towupper","wcschr","KeEnterCriticalRegion","KeLeaveCriticalRegion","ProbeForRead","RtlVolumeDeviceToDosName","ObQueryNameString","ZwQueryInformationProcess","RtlTimeFieldsToTime","ZwQueryInformationFile","ZwCreateSection","ZwMapViewOfSection","ZwUnmapViewOfSection","ObOpenObjectByPointer","PsGetThreadProcessId","ZwSetSecurityObject","IoDeviceObjectType","IoCreateDevice","RtlGetDaclSecurityDescriptor","RtlGetGroupSecurityDescriptor","RtlGetOwnerSecurityDescriptor","RtlGetSaclSecurityDescriptor","SeCaptureSecurityDescriptor","_snwprintf","RtlLengthSecurityDescriptor","SeExports","RtlCreateSecurityDescriptor","_wcsnicmp","RtlAbsoluteToSelfRelativeSD","RtlAddAccessAllowedAce","RtlLengthSid","IoIsWdmVersionAvailable","RtlSetDaclSecurityDescriptor","PsGetCurrentProcessId","ExWaitForRundownProtectionRelease","ExRundownCompleted","ExReleaseRundownProtection","ExAcquireRundownProtection","ExInitializeRundownProtection","__C_specific_handler","IoQueueWorkItem","IoFreeWorkItem","IoAllocateWorkItem","PsLookupProcessByProcessId","SeLocateProcessImageName","RtlUpcaseUnicodeString","ZwQuerySymbolicLinkObject","ZwOpenSymbolicLinkObject","ZwClose","ObfDereferenceObject","FsRtlDissectName","PsThreadType","PsProcessType","IoThreadToProcess","_vsnwprintf","RtlDowncaseUnicodeString","ExUuidCreate","KeReleaseSpinLock","KeAcquireSpinLockRaiseToDpc","KeWaitForSingleObject","KeReleaseSemaphore","KeInitializeSemaphore","RtlFreeUnicodeString","RtlCopyUnicodeString","PsGetProcessId","RtlPrefixUnicodeString","IoGetCurrentProcess","ExDeleteResourceLite","ExInitializeResourceLite","RtlEqualUnicodeString","ExReleaseResourceAndLeaveCriticalRegion","ExEnterCriticalRegionAndAcquireResourceExclusive","ExEnterCriticalRegionAndAcquireResourceShared","ExFreePoolWithTag","ExAllocatePoolWithTag","RtlInitUnicodeString","PsGetCurrentThreadId","ObfReferenceObject","KeBugCheckEx","BCryptOpenAlgorithmProvider","BCryptGetProperty","BCryptCloseAlgorithmProvider","BCryptImportKeyPair","BCryptDestroyKey","BCryptVerifySignature","BCryptCreateHash","BCryptHashData","BCryptFinishHash","BCryptDestroyHash","FltGetFileNameInformation","FltReleaseFileNameInformation","FltParseFileNameInformation","FltCreateFile","FltClose","FltFindExtraCreateParameter","FltGetEcpListFromCallbackData","FltIsEcpFromUserMode","FltGetInstanceContext","FltReleaseContext","FltEnumerateInstances","FltGetVolumeInformation","FltDeleteInstanceContext","FltSetInstanceContext","FltGetRequestorProcessId","FltCloseCommunicationPort","FltGetStreamHandleContext","FltSetStreamHandleContext","FltAllocateContext","FltIsDirectory","FltGetDestinationFileNameInformation","FltStartFiltering","FltUnreg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ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Hardware Compatibility Publisher","ValidFrom":"2024-05-16 22:16:06","ValidTo":"2025-05-14 22:16:06","Signature":"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","SignatureAlgorithmOID":"1.2.840.113549.1.1.11","IsCertificateAuthority":false,"SerialNumber":"33000001112a0790aae5568529000000000111","Version":3,"CertificateType":"Leaf (Code 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23:58:38","Signature":"5a8a67daccd5fd0d264177bf0a4678b4b3de12692b7723c2652f015fd203f461ba509d2e8c3972f36c3e6ab11e766decb7f382dcccbbc56970287366173f54ebee011648c446d91b80ae813a8d0f796d68b09eea2d3f39d3ca387ebd5e7c086e19dcc6c2f438336861e2524783e1000156d2bacb878205310a418b4ee77f5f5fed5fd3392d45eba213bffd1ec298417161165fc80a70257c59693124e471e70abb0417f79f721ec9d2bb1abe3d02fe090cb243b4591a99539396215fe0d6b72601429536ac27fdbef48577683d18bdf4be98882211865216f345ec0397107087a37043713cdbc98603170cf5735bc67de15c64edd7c548d7ed32e2d1aad3cfa7f6574e61f977eb67f288b3de00da038fd08a34373e1dd862b8d2b1f3e12f8b723b81967c6ffcec667672601b24f2a0896d5b6d002eef28dd868705c2b4b9e5be64c22af24a155c98e2c42785ff52e3627e0fb2020bd766c70ab2d33d200414503259830a7d9bed5a38120152ba2f5e20728e4af1fde771028c3be107bec973f4dd47d8b4efb4a4b330b9893e76cab90098567eabea8ab8a5d038ab6977130b142fe9aa411ff7babd3a2b348aee0aab63e663f788248e200d2b3b9de3c24952ac9f1f0e393b5dd46e506ae67d523aaa7c3315290d265e0158a74ea93d7a846f743f609fe4324f3600af6d71d33ea646655f8174f1fec171da4ca0415a82ddf11f","SignatureAlgorithmOID":"1.2.840.113549.1.1.11","IsCertificateAuthority":true,"SerialNumber":"610baac1000000000009","Version":3,"CertificateType":"CA","IsCodeSigning":false,"IsCA":true,"TBS":{"MD5":"a569061297e8e824767dbc3184a69bea","SHA1":"adbb26a587a8f44b4fccaecb306f980d1c55a150","SHA256":"cec1afd0e310c55c1dcc601ab8e172917706aa32fb5eaf826813547fdf02dd46","SHA384":"e947cac936803f5683196e4ff1b259096073395d0b908522ddce90d57597c9f7b57f7ddcdbe021ba863d843c340da8ba"}}],"Signer":[{"SerialNumber":"33000001112a0790aae5568529000000000111","Issuer":"C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Third Party Component CA 2012","Version":1}]}],"Signature":["Microsoft Windows Hardware Compatibility Publisher"]}]}