5cbb1918-f7ac-4de8-b334-0bb4824a516b

rksafe.sys :inline

Description

Nextron Systems identifies this rksafe sample as a rootkit with input interception, anti-debugging, minifilter callbacks, and process protection. Static analysis confirms cross-process memory read/write routines, minifilter registration with a communication port, process and thread object callbacks, and logic that clears KdDebuggerEnabled. Input interception and successful runtime protection effects were not independently tested.

  • UUID: 5cbb1918-f7ac-4de8-b334-0bb4824a516b
  • Created: 2026-09-08
  • Author: Michael Haag
  • Acknowledgement: Nextron Systems Research | @nextronresearch

Download

This download link contains the malicious driver!

Block rksafe.sys across your endpoints

Add this driver to your block policy in minutes with MagicSword, threat-driven application control. Free for up to 100 endpoints.

Start Blocking for Free
Use CasePrivilegesOperating System
Read and modify process memory and interfere with kernel debugging.kernelWindows x64

Detections

YARA 🏹

Expand

Exact Match

with header and size limitation

Threat Hunting

without header and size limitation

Sigma 🛡️

Expand

Names

detects loading using name only

Hashes

detects loading using hashes only

Sysmon 🔎

Expand

Block

on hashes

Alert

on hashes

Resources


  • https://github.com/NextronSystems/iocs/blob/89038fb97602153f20dadb9ba7e9fcaeac9af148/reports/whql-signed/readme.md

    • Known Vulnerable Samples

    PropertyValue
    Filenamerksafe.sys
    Creation Timestamp2025-07-25 01:41:57
    MD576d36fee8ee297ab69b4cfce2cd4ac52
    SHA18f6391cc23e039b0db4601ea1f67da4c77998414
    SHA25681fbcacbc28001909391dbdafd9854ca997befa38dee4f2d9e8fbdbd00bc3723
    Authentihash MD5ae42b2365f79217217dd36a1bd07617a
    Authentihash SHA1097da8ddf813a15c907f6159cb1e7dc3378cce19
    Authentihash SHA256bd97725f80debb250a388a6656c7bf79ac0c3c9eed6ce00705d9677f413dd843
    RichPEHeaderHash MD5cafee670f1692174d4f920d8f6a18b8b
    RichPEHeaderHash SHA130093b11d9d60004021a7c3a80e44b9b34e9dca1
    RichPEHeaderHash SHA2568424e9e485b6d4f723d3890a84008c9dbfc675707f16ca55f3181ce39e254ee4

    Download

    Certificates

    Expand
    Certificate 330000006daa072f958218c9e300000000006d
    FieldValue
    ToBeSigned (TBS) MD54320213204f73b9d506bbcbb35111c2d
    ToBeSigned (TBS) SHA1d3cbbc8331d4d84555a6726d48dfd9571738bd25
    ToBeSigned (TBS) SHA256fe99f47e601d6b8ab1e89961000f680bf3b0e0629a8a59864e76f135e0c89699
    SubjectC=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Hardware Compatibility Publisher
    ValidFrom2024-10-10 19:04:52
    ValidTo2025-10-08 19:04:52
    Signature1bfc71b1c6ae1f779c132566b0692231de393c7578f2ae3adafa2968f4c01599d9dde8827a1f2ec65c46c56cad36987c0df5b1ec1c36576126f5fb988923b3c7f3f111749105254facfc1831516dba7fa7265753447f94b11979a3e9aba7f5dbd87e3f0f034229a34c7fb10cb7a90f197ffd35432e4244ee7666d4a48de1586b61b1072d441cd345eb140b613fd0fef87ab5eef73985d940029d30870053909e8550e94cb4e63696e82a182a7632267efb6056cf7c7b05c108645ea8698bba379bfa31e6bf7e179edbc3e559bbfe1fa8bf5c6b0c783edebac68aefa287bd16c1fcf2e00839c693e40e79f7c63447712a321c2ca5ee1dd2a0e03bde2702d9320a50d20439f395257fb6c5af0c11432c52801127d4bc45c0a65c660f5769fdf250aaba99a74bef0885f21a040f11e6364ba7499c795b39ca0972ff857d4e7c9bc08f257cb8dadb28817b62de202f3639de9db076ad8ee6b71a3cea1a1a476a510a3197fce4592654389629c6108656d9132971b2e55f3d19963d966a6869712265b662dcc7c92d6e3659d429c814f3efdf05ded84fe8654a039222dbe133a7992e04f05d8d7642ceb159cc705b832ec2f507ba8604047a01ff37fd69397ad861ad766df8e4e296199d81d89f708550a04d774da5c1b50062e06a72badcdb12f94820b5b834442ada4a82ce25d0450a519cac28d8362bd182257b1b80cf930e92d0
    SignatureAlgorithmOID1.2.840.113549.1.1.11
    IsCertificateAuthorityFalse
    SerialNumber330000006daa072f958218c9e300000000006d
    Version3
    Certificate 330000000d690d5d7893d076df00000000000d
    FieldValue
    ToBeSigned (TBS) MD583f69422963f11c3c340b81712eef319
    ToBeSigned (TBS) SHA10c5e5f24590b53bc291e28583acb78e5adc95601
    ToBeSigned (TBS) SHA256d8be9e4d9074088ef818bc6f6fb64955e90378b2754155126feebbbd969cf0ae
    SubjectC=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Third Party Component CA 2014
    ValidFrom2014-10-15 20:31:27
    ValidTo2029-10-15 20:41:27
    Signature96b5c33b31f27b6ba11f59dd742c3764b1bca093f9f33347e9f95df21d89f4579ee33f10a3595018053b142941b6a70e5b81a2ccbd8442c1c4bed184c2c4bd0c8c47bcbd8886fb5a0896ae2c2fdfbf9366a32b20ca848a6945273f732332936a23e9fffdd918edceffbd6b41738d579cf8b46d499805e6a335a9f07e6e86c06ba8086725afc0998cdba7064d4093188ba959e69914b912178144ac57c3ae8eae947bcb3b8edd7ab4715bba2bc3c7d085234b371277a54a2f7f1ab763b94459ed9230cce47c099212111f52f51e0291a4d7d7e58f8047ff189b7fd19c0671dcf376197790d52a0fbc6c12c4c50c2066f50e2f5093d8cafb7fe556ed09d8a753b1c72a6978dcf05fe74b20b6af63b5e1b15c804e9c7aa91d4df72846782106954d32dd6042e4b61ac4f24636de357302c1b5e55fb92b59457a9243d7c4e963dd368f76c728caa8441be8321a66cde5485c4a0a602b469206609698dcd933d721777f886dac4772daa2466eab64682bd24e98fb35cc7fec3f136d11e5db77edc1c37e1f6a4a14f8b4a721c671866770cdd819a35d1fa09b9a7cc55d4d728e74077fa74d00fcdd682412772a557527cda92c1d8e7c19ee692c9f7425338208db38cc7cc74f6c3a6bc237117872fe55596460333e2edfc42de72cd7fb0a82256fb8d70c84a5e1c4746e2a95329ea0fecdb4188fd33bad32b2b19ab86d0543fbff0d0f
    SignatureAlgorithmOID1.2.840.113549.1.1.11
    IsCertificateAuthorityTrue
    SerialNumber330000000d690d5d7893d076df00000000000d
    Version3

    Imports

    Expand
    • FLTMGR.SYS
    • ntoskrnl.exe
    • WDFLDR.SYS

    Imported Functions

    Expand
    • FltCloseCommunicationPort
    • FltGetRequestorProcessId
    • FltSendMessage
    • FltRegisterFilter
    • FltUnregisterFilter
    • FltStartFiltering
    • FltGetFileNameInformation
    • FltReleaseFileNameInformation
    • FltParseFileNameInformation
    • FltCreateCommunicationPort
    • FltFreeSecurityDescriptor
    • FltCloseClientPort
    • FltBuildDefaultSecurityDescriptor
    • PsGetProcessId
    • NtClose
    • KeStackAttachProcess
    • KeUnstackDetachProcess
    • PsLookupProcessByProcessId
    • ObOpenObjectByPointer
    • PsProcessType
    • KeDelayExecutionThread
    • PsCreateSystemThread
    • PsTerminateSystemThread
    • KdDebuggerEnabled
    • RtlCompareUnicodeString
    • strlen
    • RtlInitUnicodeString
    • MmGetSystemRoutineAddress
    • wcslen
    • IoDriverObjectType
    • KeDeregisterNmiCallback
    • PsGetCurrentThreadId
    • IoGetCurrentProcess
    • ObRegisterCallbacks
    • ObUnRegisterCallbacks
    • PsThreadType
    • KeInitializeMutex
    • KeReleaseMutex
    • KeWaitForSingleObject
    • PsSetCreateProcessNotifyRoutineEx
    • ExQueryDepthSList
    • ExpInterlockedPopEntrySList
    • ExpInterlockedPushEntrySList
    • RtlGetVersion
    • ExCreateCallback
    • ExNotifyCallback
    • PsSetCreateThreadNotifyRoutineEx
    • PsRemoveCreateThreadNotifyRoutine
    • ObReferenceObjectByHandle
    • RtlInitializeGenericTableAvl
    • RtlInsertElementGenericTableAvl
    • RtlDeleteElementGenericTableAvl
    • RtlLookupElementGenericTableAvl
    • RtlEnumerateGenericTableAvl
    • RtlGetElementGenericTableAvl
    • RtlNumberGenericTableElementsAvl
    • MmMapViewInSystemSpace
    • MmUnmapViewInSystemSpace
    • RtlInitUnicodeStringEx
    • RtlImageNtHeader
    • RtlFindExportedRoutineByName
    • RtlPcToFileHeader
    • MmSectionObjectType
    • ExInitializeResourceLite
    • ExEnterCriticalRegionAndAcquireResourceShared
    • ExEnterCriticalRegionAndAcquireResourceExclusive
    • ExReleaseResourceAndLeaveCriticalRegion
    • ExDeleteResourceLite
    • ExAcquireSpinLockShared
    • ExReleaseSpinLockShared
    • ObfDereferenceObject
    • ExReleaseSpinLockExclusive
    • RtlRaiseException
    • RtlFreeUnicodeString
    • ExInitializeRundownProtection
    • ExWaitForRundownProtectionRelease
    • RtlDuplicateUnicodeString
    • RtlEqualUnicodeString
    • KeInitializeEvent
    • KeSetEvent
    • ExQueueWorkItem
    • IoQueueWorkItemEx
    • IoSizeofWorkItem
    • IoInitializeWorkItem
    • PsLoadedModuleList
    • PsLoadedModuleResource
    • RtlImageDirectoryEntryToData
    • RtlInitializeBitMap
    • RtlFindClearBitsAndSet
    • RtlClearBits
    • RtlAreBitsSet
    • _local_unwind
    • RtlNtStatusToDosErrorNoTeb
    • ExSystemExceptionFilter
    • ExInitializeLookasideListEx
    • ExDeleteLookasideListEx
    • ExRegisterCallback
    • ExUnregisterCallback
    • PsGetCurrentProcessId
    • InitializeSListHead
    • RtlUnwindEx
    • strcpy_s
    • IoGetStackLimits
    • MmIsAddressValid
    • RtlCopyUnicodeString
    • DbgPrintEx
    • KeEnterCriticalRegion
    • KeLeaveCriticalRegion
    • ExAcquireResourceExclusiveLite
    • ExReleaseResourceLite
    • ExIsProcessorFeaturePresent
    • ProbeForWrite
    • ProbeForRead
    • ExFreePoolWithTag
    • ExAllocatePoolWithTag
    • ExAcquireSpinLockExclusive
    • WdfVersionUnbindClass
    • WdfVersionBind
    • WdfVersionBindClass
    • WdfVersionUnbind
    • WdfLdrQueryInterface

    Exported Functions

    Expand

    Sections

    Expand
    • .text
    • .rdata
    • .data
    • .pdata
    • PAGE
    • INIT
    • .reloc

    Signature

    Expand
    {
  "Certificates": [
    {
      "CertificateType": "Leaf (Code Signing)",
      "IsCA": false,
      "IsCertificateAuthority": false,
      "IsCodeSigning": true,
      "SerialNumber": "330000006daa072f958218c9e300000000006d",
      "Signature": "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",
      "SignatureAlgorithmOID": "1.2.840.113549.1.1.11",
      "Subject": "C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Hardware Compatibility Publisher",
      "TBS": {
        "MD5": "4320213204f73b9d506bbcbb35111c2d",
        "SHA1": "d3cbbc8331d4d84555a6726d48dfd9571738bd25",
        "SHA256": "fe99f47e601d6b8ab1e89961000f680bf3b0e0629a8a59864e76f135e0c89699",
        "SHA384": "e0a64b97e2ac3d56d42b593fccee2d0e80fc626b8161f60a36a2adef8fe94c7c06c7509816d1c2211400626fc1fc63c7"
      },
      "ValidFrom": "2024-10-10 19:04:52",
      "ValidTo": "2025-10-08 19:04:52",
      "Version": 3
    },
    {
      "CertificateType": "CA",
      "IsCA": true,
      "IsCertificateAuthority": true,
      "IsCodeSigning": false,
      "SerialNumber": "330000000d690d5d7893d076df00000000000d",
      "Signature": "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",
      "SignatureAlgorithmOID": "1.2.840.113549.1.1.11",
      "Subject": "C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Third Party Component CA 2014",
      "TBS": {
        "MD5": "83f69422963f11c3c340b81712eef319",
        "SHA1": "0c5e5f24590b53bc291e28583acb78e5adc95601",
        "SHA256": "d8be9e4d9074088ef818bc6f6fb64955e90378b2754155126feebbbd969cf0ae",
        "SHA384": "260ad59ba706420f68ba212931153bd89f760c464b21be55fba9d014fff322407859d4ebfb78ea9a3330f60dc9821a63"
      },
      "ValidFrom": "2014-10-15 20:31:27",
      "ValidTo": "2029-10-15 20:41:27",
      "Version": 3
    }
  ],
  "CertificatesInfo": "",
  "Signer": [
    {
      "Issuer": "C=US, ST=Washington, L=Redmond, O=Microsoft Corporation, CN=Microsoft Windows Third Party Component CA 2014",
      "SerialNumber": "330000006daa072f958218c9e300000000006d",
      "Version": 1
    }
  ],
  "SignerInfo": ""
}

    source

    last_updated: 2026-09-08