Detection rules › YARA-L

Process Memory Dump via RdrLeakDiag.exe

Severity
high
Type
Detection
Time window
5m
Match by
hostname
Author
Cedric MAURUGEON, Florian Roth (Nextron Systems), Swachchhanda Shrawan Poudel, Nasreddine Bencherchali (Nextron Systems)
Source
github.com/chronicle/detection-rules

Detects the use of the Microsoft Windows Resource Leak Diagnostic tool rdrleakdiag.exe to dump process memory

MITRE ATT&CK coverage

TacticTechniques
Credential AccessT1003.001 OS Credential Dumping: LSASS Memory

References

Event coverage

Rule body yaral

/*
 * Copyright 2025 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

rule process_memory_dump_via_rdrleakdiag {

  meta:
    author = "Cedric MAURUGEON, Florian Roth (Nextron Systems), Swachchhanda Shrawan Poudel, Nasreddine Bencherchali (Nextron Systems)"
    description = "Detects the use of the Microsoft Windows Resource Leak Diagnostic tool rdrleakdiag.exe to dump process memory"
    reference = "https://github.com/SigmaHQ/sigma/blob/master/rules/windows/process_creation/proc_creation_win_rdrleakdiag_process_dumping.yml"
    license = "https://github.com/SigmaHQ/Detection-Rule-License/blob/main/LICENSE.Detection.Rules.md"
    rule_name = "Process Memory Dump via RdrLeakDiag.exe"
    sigma_uuid = "edadb1e5-5919-4e4c-8462-a9e643b02c4b"
    sigma_status = "test"
    rule_id = "mr_89eca7b6-5b7e-4bd1-978e-156bd00f5324"
    tactic = "TA0006"
    technique = "T1003.001"
    type = "Detection"
    data_source = "Windows Event Logs"
    platform = "Windows"
    severity = "High"
    priority = "High"
    false_positives = "Unlikely"

  events:
    $process.metadata.event_type = "PROCESS_LAUNCH"
    (
        re.regex($process.target.process.file.full_path, `rdrleakdiag\.exe$`) nocase or
        $process.src.process.file.full_path = "RdrLeakDiag.exe" nocase
    )
    re.regex($process.target.process.command_line, `(/|full)memdmp`) nocase
    re.regex($process.target.process.command_line, `/(o|p)`) nocase

    $process.principal.hostname = $hostname

  match:
    $hostname over 5m

  outcome:
    //example usage of specifying test user and hostname to adjust risk score
    $risk_score = max(if($process.principal.user.userid = "user" and $process.principal.hostname = "hostname", 0, 15))
    $principal_process_pid = array_distinct($process.principal.process.pid)
    $principal_process_command_line = array_distinct($process.principal.process.command_line)
    $principal_process_file_sha256 = array_distinct($process.principal.process.file.sha256)
    $principal_process_file_full_path = array_distinct($process.principal.process.file.full_path)
    $principal_process_product_specfic_process_id = array_distinct($process.principal.process.product_specific_process_id)
    $principal_process_parent_process_product_specfic_process_id = array_distinct($process.principal.process.parent_process.product_specific_process_id)
    $target_process_pid = array_distinct($process.target.process.pid)
    $target_process_command_line = array_distinct($process.target.process.command_line)
    $target_process_file_sha256 = array_distinct($process.target.process.file.sha256)
    $target_process_file_full_path = array_distinct($process.target.process.file.full_path)
    $target_process_product_specfic_process_id = array_distinct($process.target.process.product_specific_process_id)
    $principal_user_userid = array_distinct($process.principal.user.userid)
    $log_type = array_distinct(strings.concat($process.metadata.log_type,"/",$process.metadata.product_event_type))

  condition:
    $process
}

Detection logic

Fires when at least one $process event in the 5m window.

Events

$process PROCESS_LAUNCH (1, 4688)

  • target.process.file.full_path matches "rdrleakdiag\.exe$"
  • src.process.file.full_path = "RdrLeakDiag.exe"
  • target.process.command_line matches "(/|full)memdmp"
  • target.process.command_line matches "/(o|p)"

Correlation

Match key
$hostname (principal.hostname)
Within
5m

Outcome

Fields the detection emits on a match. $risk_score drives alerting; Chronicle surfaces the rest on the detection.

FieldExpression
risk_scoremax(if($process.principal.user.userid = "user" and $process.principal.hostname = "hostname", 0, 15))
principal_process_pidarray_distinct($process.principal.process.pid)
principal_process_command_linearray_distinct($process.principal.process.command_line)
principal_process_file_sha256array_distinct($process.principal.process.file.sha256)
principal_process_file_full_patharray_distinct($process.principal.process.file.full_path)
principal_process_product_specfic_process_idarray_distinct($process.principal.process.product_specific_process_id)
principal_process_parent_process_product_specfic_process_idarray_distinct($process.principal.process.parent_process.product_specific_process_id)
target_process_pidarray_distinct($process.target.process.pid)
target_process_command_linearray_distinct($process.target.process.command_line)
target_process_file_sha256array_distinct($process.target.process.file.sha256)
target_process_file_full_patharray_distinct($process.target.process.file.full_path)
target_process_product_specfic_process_idarray_distinct($process.target.process.product_specific_process_id)
principal_user_useridarray_distinct($process.principal.user.userid)
log_typearray_distinct(strings.concat($process.metadata.log_type,"/",$process.metadata.product_event_type))