Okta Non-Standard VPN Usage

Status: experimental
Severity: medium
Group by: _time, host, index, sourcetype, tunnels
Author: Marissa Bower, Raven Tait
Source: github.com/splunk/security_content

Remote Employment Fraud (REF) actors will often use virtual private networks (VPNs) to conceal their true physical location. Threat actors mask their originating IP address and instead appear to be situated in any location where the VPN service has a node.

MITRE ATT&CK coverage

Tactic	Techniques
Initial Access	`T1078` Valid Accounts
Persistence	`T1078` Valid Accounts
Privilege Escalation	`T1078` Valid Accounts
Stealth	`T1078` Valid Accounts
Command & Control	`T1090` Proxy, `T1572` Protocol Tunneling

Rule body splunk

name: Okta Non-Standard VPN Usage
id: 58eb9f80-896c-42f8-86c6-27ab59026c9c
version: 4
creation_date: '2025-06-12'
modification_date: '2026-05-13'
author: Marissa Bower, Raven Tait
status: experimental
type: TTP
description: Remote Employment Fraud (REF) actors will often use virtual private networks (VPNs) to conceal their true physical location. Threat actors mask their originating IP address and instead appear to be situated in any location where the VPN service has a node.
data_source:
    - Okta
search: '`okta` debugContext.debugData.tunnels IN (*Astrill*,*Azire*,*CyberGhost*,*Express*VPN,*HideMe*, *IPVanish*,*Mullvad*,*Nord*VPN*,*OVPN*,*PIA*VPN*,*Proton*VPN*,*Pure*VPN*,*Slick*VPN*,*Surf*Easy*, *SurfShark*,*Star*VPN*,*TorGuard*,*TorProxy*,*Tiger*VPN*,*TunnelBear*,*Unblock*VPN*,*Warp*VPN*,*WarpSpeed*, *VPNReactor*,*VPN*Shield*,*VPN*Super*VPN*,*ZenMate*) ```listing of commonly used known VPN providers. Add or remove whatever is appropriate for your environment``` | eval user=coalesce(''actor.alternateId'',user), user=mvindex(split(user, "@"), 0) | rename targetUserAlternateId as user client.* as * request.* as * ipChain{}.* as * geographicalContext.* as * debugContext.* as * debugData.* as * | eval status=case(match(_raw, "FAILURE"), "failure", !match(_raw, "FAILURE"), "success") | stats count values(status) as status max(published) as UTC min(_time) as firsttime max(_time) as lasttime values(target_data) as target_data values(displayMessage) as displayMessage values(eventType) as eventType values(city) as city values(country) as country values(action) as action values(src_ip) as src_ip values(outcome.*) as * values(user) as user by tunnels,_time,host sourcetype index | fillnull value="N/A" | convert ctime(*ttime) | `okta_non_standard_vpn_usage_filter`'
how_to_implement: The analytic leverages Okta OktaIm2 logs to be ingested using the Splunk Add-on for Okta Identity Cloud (https://splunkbase.splunk.com/app/6553).
known_false_positives: Limited to no expected false positives once a baseline of common VPN software has been completed.
drilldown_searches:
    - name: View the detection results for - "$user$"
      search: '%original_detection_search% | search  actor.alternateId = "$user$"'
      earliest_offset: $info_min_time$
      latest_offset: $info_max_time$
    - name: View risk events for the last 7 days for - "$user$"
      search: '| from datamodel Risk.All_Risk | search normalized_risk_object IN ("$user$") | stats count min(_time) as firstTime max(_time) as lastTime values(search_name) as "Search Name" values(risk_message) as "Risk Message" values(analyticstories) as "Analytic Stories" values(annotations._all) as "Annotations" values(annotations.mitre_attack.mitre_tactic) as "ATT&CK Tactics" by normalized_risk_object | `security_content_ctime(firstTime)` | `security_content_ctime(lastTime)`'
      earliest_offset: 7d
      latest_offset: "0"
finding:
    title: Uncommon VPN software used by $user$ to connect to Okta.
    entity:
        field: user
        type: user
        score: 50
analytic_story:
    - Remote Employment Fraud
    - Suspicious Okta Activity
asset_type: Identity
mitre_attack_id:
    - T1078
    - T1572
    - T1090
product:
    - Splunk Enterprise
    - Splunk Enterprise Security
    - Splunk Cloud
category: cloud
security_domain: identity

Stages and Predicates

Stage 1: `search`

`okta` debugContext.debugData.tunnels IN (*Astrill*,*Azire*,*CyberGhost*,*Express*VPN,*HideMe*, *IPVanish*,*Mullvad*,*Nord*VPN*,*OVPN*,*PIA*VPN*,*Proton*VPN*,*Pure*VPN*,*Slick*VPN*,*Surf*Easy*, *SurfShark*,*Star*VPN*,*TorGuard*,*TorProxy*,*Tiger*VPN*,*TunnelBear*,*Unblock*VPN*,*Warp*VPN*,*WarpSpeed*, *VPNReactor*,*VPN*Shield*,*VPN*Super*VPN*,*ZenMate*)

Stage 2: `eval`

| eval user=coalesce('actor.alternateId',user), user=mvindex(split(user, "@"), 0)

Stage 3: `rename`

| rename targetUserAlternateId as user client.* as * request.* as * ipChain{}.* as * geographicalContext.* as * debugContext.* as * debugData.* as *

Stage 4: `eval`

| eval status=case(match(_raw, "FAILURE"), "failure", !match(_raw, "FAILURE"), "success")

status =

ifmatch(_raw, "FAILURE")"failure"

else"success"

Stage 5: `stats`

| stats count values(status) as status max(published) as UTC min(_time) as firsttime max(_time) as lasttime values(target_data) as target_data values(displayMessage) as displayMessage values(eventType) as eventType values(city) as city values(country) as country values(action) as action values(src_ip) as src_ip values(outcome.*) as * values(user) as user by tunnels,_time,host sourcetype index

Stage 6: `fillnull`

| fillnull value="N/A"

Stage 7: `convert`

| convert ctime(*ttime)

Stage 8: `search`

| `okta_non_standard_vpn_usage_filter`

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
`debugContext.debugData.tunnels`	in	`Astrill` `Azire` `CyberGhost` `ExpressVPN` `HideMe` `IPVanish` `Mullvad` `NordVPN` `OVPN` `PIAVPN` `ProtonVPN` `PureVPN` `SlickVPN` `StarVPN` `SurfEasy` `SurfShark` `TigerVPN` `TorGuard` `TorProxy` `TunnelBear` `UnblockVPN` `VPNShield` `VPNSuperVPN` `VPNReactor` `WarpVPN` `WarpSpeed` `ZenMate*`
`sourcetype`	eq	`OktaIM2:log`

`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)

Okta Non-Standard VPN Usage

MITRE ATT&CK coverage

Rule body splunk

Stages and Predicates

Stage 1: `search`

Stage 2: `eval`

Stage 3: `rename`

Stage 4: `eval`

Stage 5: `stats`

Stage 6: `fillnull`

Stage 7: `convert`

Stage 8: `search`

Indicators

Keyboard shortcuts

Search operators

Okta Non-Standard VPN Usage

MITRE ATT&CK coverage

Rule body splunk

Stages and Predicates

Stage 1: search

Stage 2: eval

Stage 3: rename

Stage 4: eval

Stage 5: stats

Stage 6: fillnull

Stage 7: convert

Stage 8: search

Indicators

Stage 1: `search`

Stage 2: `eval`

Stage 3: `rename`

Stage 4: `eval`

Stage 5: `stats`

Stage 6: `fillnull`

Stage 7: `convert`

Stage 8: `search`