sap data changed during debugging

// Copyright 2026 Google LLC. Licensed under Apache-2.0.

rule sap_data_changed_during_debugging {

  meta:
    author = "Google Cloud Security"
    description = "Detects in-memory data changes (CUL) during an ABAP debugging session. Identifies if the debugger is the same as the session owner."
    severity = "Critical"
    tactic = "TA0005"
    technique = "T1564"

  events:
    $e.metadata.log_type = "SAP_SECURITY_AUDIT"

    $e.additional.fields["msg_1"] = "CUL"

    $debugger = $e.additional.fields["param1_1"]
    $session_owner = $e.principal.user.userid

    // exclusions
    not $debugger in %sap_admin_users.user

  match:
    $session_owner over 30m

  outcome:
    $risk_score = 90
    $target_sid = array_distinct($e.target.application)
    $debugging_user = array_distinct($debugger)
    $source_user = array_distinct($session_owner)

    $source_user_is_debugger = array_distinct(if($debugger = $session_owner, "true", "false"))

    $change_field = array_distinct($e.additional.fields["param2_1"])
    $change = array_distinct($e.additional.fields["param3_1"])
    $method = array_distinct(re.capture($e.additional.fields["paramx_1"], `Meth:(.*?),\s`))

  condition:
    $e
}