# [CRIT] Bitwarden CLI Hijacked on npm: Bun-Staged Credential Stealer Targets Developers, GitHub Actions, and AI Tools

**Source:** StepSecurity
**Published:** 2026-05-04
**Article:** https://www.stepsecurity.io/blog/bitwarden-cli-hijacked-on-npm-bun-staged-credential-stealer-targets-developers-github-actions-and-ai-tools

## Threat Profile

Back to Blog Threat Intel Bitwarden CLI Hijacked on npm: Bun-Staged Credential Stealer Targets Developers, GitHub Actions, and AI Tools @bitwarden/cli@2026.4.0 — the official command-line interface for the Bitwarden password manager — was found compromised on npm. A malicious preinstall hook silently bootstraps the Bun JavaScript runtime and launches a 9.7 MB obfuscated credential stealer that targets developer secrets, GitHub Actions environments, and — explicitly — AI coding tool configuration…

## Indicators of Compromise (high-fidelity only)

- **IPv4 (defanged):** `94.154.172.43`
- **Domain (defanged):** `audit.checkmarx.cx`
- **SHA256:** `18f784b3bc9a0bcdcb1a8d7f51bc5f54323fc40cbd874119354ab609bef6e4cb`
- **SHA256:** `8605e365edf11160aad517c7d79a3b26b62290e5072ef97b102a01ddbb343f14`

## MITRE ATT&CK Techniques

- **T1071.001** — Web Protocols
- **T1071.004** — DNS
- **T1071** — Application Layer Protocol
- **T1528** — Steal Application Access Token
- **T1098.001** — Account Manipulation: Additional Cloud Credentials
- **T1566.002** — Spearphishing Link
- **T1204.001** — User Execution: Malicious Link
- **T1059.001** — PowerShell
- **T1204.004** — User Execution: Malicious Copy and Paste
- **T1027** — Obfuscated Files or Information
- **T1195.002** — Compromise Software Supply Chain
- **T1204.002** — User Execution: Malicious File
- **T1059.007** — Command and Scripting Interpreter: JavaScript
- **T1105** — Ingress Tool Transfer
- **T1041** — Exfiltration Over C2 Channel
- **T1071.001** — Application Layer Protocol: Web Protocols
- **T1573.001** — Encrypted Channel: Symmetric Cryptography

## Kill chain phases observed

_(none detected from narrative keywords)_

## Recommended hunts

### Bun runtime fetched from github.com/oven-sh/bun during npm install (Bitwarden CLI hijack)

`UC_335_9` · phase: **delivery** · confidence: **High** · AI-generated for this article

**Splunk SPL (CIM):**
```spl
| tstats summariesonly=t count min(_time) as firstTime max(_time) as lastTime values(Processes.process) as cmd values(Processes.parent_process_name) as parent values(All_Traffic.dest) as dest from datamodel=Endpoint.Processes where Processes.parent_process_name IN ("npm.exe","npm-cli.js","node.exe","yarn.exe","pnpm.exe") AND (Processes.process="*bw_setup.js*" OR Processes.process="*oven-sh/bun*" OR Processes.process="*bun-v1.3.13*") by host Processes.user Processes.process_name | `drop_dm_object_name(Processes)`
```

**Defender KQL:**
```kql
let LookbackDays = 7d;
let BunDownload = DeviceNetworkEvents
| where Timestamp > ago(LookbackDays)
| where RemoteUrl has_any ("github.com/oven-sh/bun/releases","oven-sh/bun/releases/download") or RemoteUrl has "bun-v1.3.13"
| where InitiatingProcessFileName in~ ("node.exe","node","npm.exe","npm-cli.js","yarn.exe","pnpm.exe")
| project Timestamp, DeviceId, DeviceName, InitiatingProcessFileName, InitiatingProcessCommandLine, RemoteUrl, RemoteIP;
let Preinstall = DeviceProcessEvents
| where Timestamp > ago(LookbackDays)
| where ProcessCommandLine has_any ("bw_setup.js","@bitwarden/cli")
   or (FileName =~ "node.exe" and InitiatingProcessFileName in~ ("npm.exe","npm-cli.js","yarn.exe","pnpm.exe") and ProcessCommandLine has "preinstall")
| project Timestamp, DeviceId, DeviceName, AccountName, FileName, ProcessCommandLine, InitiatingProcessFileName, InitiatingProcessCommandLine;
BunDownload
| join kind=inner Preinstall on DeviceId
| where abs(datetime_diff('second', Timestamp, Timestamp1)) <= 120
| project Timestamp, DeviceName, AccountName=tostring(AccountName), InitiatingProcessFileName, RemoteUrl, RemoteIP, PreinstallCmd=ProcessCommandLine
| order by Timestamp desc
```

### TeamPCP @bitwarden/cli stealer exfil to audit.checkmarx.cx (94.154.172.43)

`UC_335_10` · phase: **c2** · confidence: **Medium** · AI-generated for this article

**Splunk SPL (CIM):**
```spl
| tstats summariesonly=t count min(_time) as firstTime max(_time) as lastTime values(All_Traffic.src) as src values(All_Traffic.dest_ip) as dest_ip values(All_Traffic.app) as app from datamodel=Network_Traffic.All_Traffic where All_Traffic.dest="audit.checkmarx.cx" OR All_Traffic.dest_ip="94.154.172.43" OR All_Traffic.url="*audit.checkmarx.cx*" by host All_Traffic.user | `drop_dm_object_name(All_Traffic)`
```

**Defender KQL:**
```kql
let Lookback = 30d;
let BadHost = dynamic(["audit.checkmarx.cx"]);
let BadIP   = dynamic(["94.154.172.43"]);
union isfuzzy=true
  (DeviceNetworkEvents
   | where Timestamp > ago(Lookback)
   | where RemoteUrl has_any (BadHost) or RemoteIP in (BadIP)
   | project Timestamp, DeviceId, DeviceName, AccountName=InitiatingProcessAccountName, InitiatingProcessFileName, InitiatingProcessCommandLine, RemoteUrl, RemoteIP, RemotePort, Source="DeviceNetworkEvents"),
  (DeviceEvents
   | where Timestamp > ago(Lookback)
   | where ActionType =~ "DnsQueryResponse" or ActionType startswith "Dns"
   | where AdditionalFields has "audit.checkmarx.cx"
   | project Timestamp, DeviceId, DeviceName, AccountName, InitiatingProcessFileName, InitiatingProcessCommandLine, RemoteUrl=tostring(parse_json(AdditionalFields).DnsQueryString), RemoteIP=tostring(parse_json(AdditionalFields).IPAddresses), RemotePort=int(null), Source="DeviceEvents-DNS")
| order by Timestamp desc
```

### Known-malicious bw_setup.js / bw1.js SHA256 dropped under @bitwarden/cli

`UC_335_11` · phase: **install** · confidence: **High** · AI-generated for this article

**Splunk SPL (CIM):**
```spl
| tstats summariesonly=t count min(_time) as firstTime max(_time) as lastTime values(Filesystem.file_path) as paths values(Filesystem.user) as user from datamodel=Endpoint.Filesystem where Filesystem.file_hash IN ("18f784b3bc9a0bcdcb1a8d7f51bc5f54323fc40cbd874119354ab609bef6e4cb","8605e365edf11160aad517c7d79a3b26b62290e5072ef97b102a01ddbb343f14") OR Filesystem.file_name IN ("bw_setup.js","bw1.js") by host Filesystem.file_name | `drop_dm_object_name(Filesystem)`
```

**Defender KQL:**
```kql
let BadHashes = dynamic(["18f784b3bc9a0bcdcb1a8d7f51bc5f54323fc40cbd874119354ab609bef6e4cb","8605e365edf11160aad517c7d79a3b26b62290e5072ef97b102a01ddbb343f14"]);
union isfuzzy=true
  (DeviceFileEvents
   | where Timestamp > ago(30d)
   | where SHA256 in (BadHashes) or (FileName in~ ("bw_setup.js","bw1.js") and FolderPath has "@bitwarden\\cli")
   | project Timestamp, DeviceId, DeviceName, ActionType, FileName, FolderPath, SHA256, Initiator=InitiatingProcessFileName, InitiatorCmd=InitiatingProcessCommandLine, User=InitiatingProcessAccountName),
  (DeviceProcessEvents
   | where Timestamp > ago(30d)
   | where SHA256 in (BadHashes) or ProcessCommandLine has_any ("bw_setup.js","bw1.js")
   | project Timestamp, DeviceId, DeviceName, ActionType, FileName, FolderPath, SHA256, Initiator=InitiatingProcessFileName, InitiatorCmd=InitiatingProcessCommandLine, User=AccountName)
| order by Timestamp desc
```

### Beaconing — periodic outbound to small set of destinations

`UC_BEACONING` · phase: **c2** · confidence: **Medium**

**Splunk SPL (CIM):**
```spl
| tstats `summariesonly` count, values(All_Traffic.dest_port) AS ports
    from datamodel=Network_Traffic.All_Traffic
    where All_Traffic.action="allowed" AND All_Traffic.dest_category!="internal"
    by _time span=10s, All_Traffic.src, All_Traffic.dest
| `drop_dm_object_name(All_Traffic)`
| streamstats current=f last(_time) AS prev_time by src, dest
| eval delta = _time - prev_time
| stats avg(delta) AS avg_delta stdev(delta) AS sd_delta count by src, dest
| where count > 30 AND sd_delta < 5 AND avg_delta>=30 AND avg_delta<=600
| sort - count
```

**Defender KQL:**
```kql
DeviceNetworkEvents
| where Timestamp > ago(1d)
| where RemoteIPType == "Public" and ActionType == "ConnectionSuccess"
| project DeviceName, RemoteIP, RemotePort, Timestamp
| sort by DeviceName asc, RemoteIP asc, RemotePort asc, Timestamp asc
| extend prev_dev = prev(DeviceName, 1), prev_ip = prev(RemoteIP, 1),
         prev_port = prev(RemotePort, 1), prev_ts = prev(Timestamp, 1)
| where DeviceName == prev_dev and RemoteIP == prev_ip and RemotePort == prev_port
| extend delta_sec = datetime_diff('second', Timestamp, prev_ts)
| summarize conn_count = count(), avg_delta = avg(delta_sec), stdev_delta = stdev(delta_sec)
    by DeviceName, RemoteIP, RemotePort
| where conn_count > 30 and avg_delta between (30.0 .. 600.0) and stdev_delta < 5.0
| order by conn_count desc
```

### OAuth consent / suspicious app grant

`UC_OAUTH_ABUSE` · phase: **actions** · confidence: **High**

**Splunk SPL (CIM):**
```spl
| tstats `summariesonly` count min(_time) as firstTime max(_time) as lastTime
    from datamodel=Authentication.Authentication
    where Authentication.action="success"
      AND Authentication.signature IN (
        "Consent to application",
        "Add app role assignment grant to user",
        "Add OAuth2PermissionGrant",
        "Add delegated permission grant")
    by Authentication.user, Authentication.app, Authentication.src, Authentication.signature
| `drop_dm_object_name(Authentication)`
```

**Defender KQL:**
```kql
CloudAppEvents
| where Timestamp > ago(7d)
| where ActionType in ("Consent to application.","Add OAuth2PermissionGrant.","Add delegated permission grant.")
| project Timestamp, AccountObjectId, AccountDisplayName, ActivityType,
          ActivityObjects, IPAddress, UserAgent
```

### Phishing-link click correlated to endpoint execution

`UC_PHISH_LINK` · phase: **delivery** · confidence: **High**

**Splunk SPL (CIM):**
```spl
``` Phishing-link click that drives endpoint execution within 60s ```
| tstats `summariesonly` earliest(_time) AS click_time
    from datamodel=Web
    where Web.action="allowed"
    by Web.src, Web.user, Web.dest, Web.url
| `drop_dm_object_name(Web)`
| rename user AS recipient, dest AS clicked_domain, url AS clicked_url
| join type=inner recipient
    [| tstats `summariesonly` count
         from datamodel=Email.All_Email
         where All_Email.action="delivered" AND All_Email.url!="-"
         by All_Email.recipient, All_Email.src_user, All_Email.url, All_Email.subject
     | `drop_dm_object_name(All_Email)`
     | rex field=url "https?://(?<email_domain>[^/]+)"
     | rename recipient AS recipient]
| join type=inner src
    [| tstats `summariesonly` earliest(_time) AS exec_time
         values(Processes.process) AS exec_cmd, values(Processes.process_name) AS exec_proc
         from datamodel=Endpoint.Processes
         where Processes.parent_process_name IN ("chrome.exe","msedge.exe","firefox.exe",
                                                   "outlook.exe","brave.exe","arc.exe")
           AND Processes.process_name IN ("powershell.exe","pwsh.exe","cmd.exe","mshta.exe",
                                            "rundll32.exe","regsvr32.exe","wscript.exe",
                                            "cscript.exe","bitsadmin.exe","certutil.exe",
                                            "curl.exe","wget.exe")
         by Processes.dest, Processes.user
     | `drop_dm_object_name(Processes)`
     | rename dest AS src]
| eval delta_sec = exec_time - click_time
| where delta_sec >= 0 AND delta_sec <= 60
| table click_time, exec_time, delta_sec, recipient, src, src_user, subject,
        clicked_domain, clicked_url, exec_proc, exec_cmd
| sort - click_time
```

**Defender KQL:**
```kql
// Phishing-link click that drives endpoint execution within 60s.
// Far higher fidelity than "every clicked URL" — most legitimate clicks
// never spawn a non-browser child process, so the join eliminates the
// 99% of noise that makes a raw click query unactionable.
let LookbackDays = 7d;
let SuspectClicks = UrlClickEvents
    | where Timestamp > ago(LookbackDays)
    | where AccountName !endswith "$"
    | where ActionType in ("ClickAllowed","ClickedThrough")
    | join kind=inner (
        EmailEvents
        | where Timestamp > ago(LookbackDays)
        | where DeliveryAction == "Delivered"
        | where EmailDirection == "Inbound"
        | project NetworkMessageId, Subject, SenderFromAddress, SenderFromDomain,
                  RecipientEmailAddress, EmailTimestamp = Timestamp
      ) on NetworkMessageId
    | join kind=leftouter (
        EmailUrlInfo | project NetworkMessageId, Url, UrlDomain
      ) on NetworkMessageId, Url
    | project ClickTime = Timestamp, AccountUpn, IPAddress, Url, UrlDomain,
              Subject, SenderFromAddress, SenderFromDomain, RecipientEmailAddress,
              ActionType;
// Correlate to a non-browser child process spawned within 60 seconds on
// the recipient's device.
DeviceProcessEvents
| where Timestamp > ago(LookbackDays)
| where InitiatingProcessFileName in~ ("chrome.exe","msedge.exe","firefox.exe",
                                         "outlook.exe","brave.exe","arc.exe")
| where FileName in~ ("powershell.exe","pwsh.exe","cmd.exe","mshta.exe",
                        "rundll32.exe","regsvr32.exe","wscript.exe","cscript.exe",
                        "bitsadmin.exe","certutil.exe","curl.exe","wget.exe")
| join kind=inner SuspectClicks on $left.AccountName == $right.AccountUpn
| where Timestamp between (ClickTime .. ClickTime + 60s)
| project ClickTime, ProcessTime = Timestamp,
          DelaySec = datetime_diff('second', Timestamp, ClickTime),
          DeviceName, AccountName, RecipientEmailAddress, SenderFromAddress,
          Subject, Url, UrlDomain, ActionType,
          FileName, ProcessCommandLine, InitiatingProcessFileName
| order by ClickTime desc
```

### Fake CAPTCHA / clipboard-injected PowerShell (ClickFix / FakeCaptcha)

`UC_FAKECAPTCHA` · phase: **exploit** · confidence: **High**

**Splunk SPL (CIM):**
```spl
| tstats `summariesonly` count min(_time) as firstTime max(_time) as lastTime
    from datamodel=Endpoint.Processes
    where Processes.parent_process_name IN ("explorer.exe","RuntimeBroker.exe")
      AND Processes.process_name IN ("powershell.exe","pwsh.exe","mshta.exe")
      AND (Processes.process="*iex*" OR Processes.process="*Invoke-Expression*"
        OR Processes.process="*FromBase64*" OR Processes.process="*DownloadString*"
        OR Processes.process="*hxxp*" OR Processes.process="*curl*" OR Processes.process="*wget*")
    by Processes.dest, Processes.user, Processes.process, Processes.parent_process_name
| `drop_dm_object_name(Processes)`
```

**Defender KQL:**
```kql
DeviceProcessEvents
| where Timestamp > ago(7d)
| where AccountName !endswith "$"
| where InitiatingProcessFileName in~ ("explorer.exe","RuntimeBroker.exe")
| where FileName in~ ("powershell.exe","pwsh.exe","mshta.exe")
| where ProcessCommandLine matches regex @"(?i)(iex|invoke-expression|frombase64|downloadstring|hxxp|curl |wget )"
| project Timestamp, DeviceName, AccountName, ProcessCommandLine, InitiatingProcessCommandLine
```

### PowerShell encoded / obfuscated command

`UC_PS_OBFUSCATED` · phase: **exploit** · confidence: **High**

**Splunk SPL (CIM):**
```spl
| tstats `summariesonly` count min(_time) as firstTime max(_time) as lastTime
    from datamodel=Endpoint.Processes
    where Processes.process_name IN ("powershell.exe","pwsh.exe")
      AND (Processes.process="*-enc *" OR Processes.process="*EncodedCommand*"
        OR Processes.process="*FromBase64String*" OR Processes.process="*-nop*"
        OR Processes.process="*-w hidden*" OR Processes.process="*Invoke-Expression*"
        OR Processes.process="*IEX(*" OR Processes.process="*DownloadString*"
        OR Processes.process="*Net.WebClient*")
    by Processes.dest, Processes.user, Processes.process_name, Processes.process, Processes.parent_process_name
| `drop_dm_object_name(Processes)`
```

**Defender KQL:**
```kql
DeviceProcessEvents
| where Timestamp > ago(7d)
| where AccountName !endswith "$"
| where FileName in~ ("powershell.exe","pwsh.exe")
| where ProcessCommandLine matches regex @"(?i)(-enc|encodedcommand|frombase64string|-nop|-w\s+hidden|invoke-expression|iex\s*\(|downloadstring|net\.webclient)"
| project Timestamp, DeviceName, AccountName, ProcessCommandLine,
          InitiatingProcessFileName, InitiatingProcessCommandLine
```

### Trusted vendor binary / installer launching unusual children

`UC_SUPPLY_CHAIN` · phase: **exploit** · confidence: **Medium**

**Splunk SPL (CIM):**
```spl
| tstats `summariesonly` count min(_time) as firstTime max(_time) as lastTime
    from datamodel=Endpoint.Processes
    where Processes.parent_process_name IN ("setup.exe","installer.exe","update.exe")
      AND Processes.process_name IN ("powershell.exe","cmd.exe","rundll32.exe","regsvr32.exe","mshta.exe","wscript.exe","cscript.exe","wmic.exe","bitsadmin.exe")
    by Processes.dest, Processes.user, Processes.parent_process_name, Processes.process_name, Processes.process
| `drop_dm_object_name(Processes)`
```

**Defender KQL:**
```kql
DeviceProcessEvents
| where Timestamp > ago(7d)
| where AccountName !endswith "$"
| where InitiatingProcessFileName in~ ("setup.exe","installer.exe","update.exe")
| where FileName in~ ("powershell.exe","cmd.exe","rundll32.exe","regsvr32.exe","mshta.exe","wscript.exe","cscript.exe","wmic.exe","bitsadmin.exe")
| project Timestamp, DeviceName, AccountName, InitiatingProcessFileName, FileName, ProcessCommandLine
```

### Article-specific behavioural hunt — Bitwarden CLI Hijacked on npm: Bun-Staged Credential Stealer Targets Developers,

`UC_335_8` · phase: **exploit** · confidence: **High**

**Splunk SPL (CIM):**
```spl
``` Article-specific bespoke detection — Bitwarden CLI Hijacked on npm: Bun-Staged Credential Stealer Targets Developers, ```
| tstats `summariesonly` count earliest(_time) AS firstTime latest(_time) AS lastTime
    from datamodel=Endpoint.Processes
    where (Processes.process_name IN ("bw_setup.js","bw1.js","node.js"))
    by Processes.dest, Processes.user, Processes.process_name,
       Processes.process, Processes.parent_process_name, Processes.process_path
| `drop_dm_object_name(Processes)`
| `security_content_ctime(firstTime)`
| append [
| tstats `summariesonly` count
    from datamodel=Endpoint.Filesystem
    where Filesystem.action IN ("created","modified")
      AND (Filesystem.file_path="*/dev/null*" OR Filesystem.file_name IN ("bw_setup.js","bw1.js","node.js"))
    by Filesystem.dest, Filesystem.user, Filesystem.process_name,
       Filesystem.file_path, Filesystem.file_name
| `drop_dm_object_name(Filesystem)`
]
```

**Defender KQL:**
```kql
// Article-specific bespoke detection — Bitwarden CLI Hijacked on npm: Bun-Staged Credential Stealer Targets Developers,
// Hunts the actual binaries / paths / commandline fragments named
// in the article instead of a generic technique-class template.
DeviceProcessEvents
| where Timestamp > ago(30d)
| where (FileName in~ ("bw_setup.js", "bw1.js", "node.js"))
| project Timestamp, DeviceName, AccountName, FileName,
          FolderPath, ProcessCommandLine,
          InitiatingProcessFileName, InitiatingProcessCommandLine
| order by Timestamp desc

// File-creation events for the named binaries / paths
DeviceFileEvents
| where Timestamp > ago(30d)
| where ActionType in ("FileCreated","FileModified")
| where (FolderPath has_any ("/dev/null") or FileName in~ ("bw_setup.js", "bw1.js", "node.js"))
| project Timestamp, DeviceName, AccountName, FolderPath,
          FileName, ActionType, InitiatingProcessFileName,
          InitiatingProcessCommandLine
| order by Timestamp desc
```

### IOC-driven hunts (use shared templates)

These are standard IOC-substitution hunts — the canonical SPL and KQL live once in [`_TEMPLATES.md`](../_TEMPLATES.md), so we don't repeat the same boilerplate on every CVE / hash / network-IOC briefing.

- **Network connections to article IPs / domains** ([template](../_TEMPLATES.md#network-ioc)) — phase: **c2**, confidence: **High**
  - IP / domain IOC(s): `94.154.172.43`, `audit.checkmarx.cx`

- **File hash IOCs — endpoint file/process match** ([template](../_TEMPLATES.md#hash-ioc)) — phase: **install**, confidence: **High**
  - file hash IOC(s): `18f784b3bc9a0bcdcb1a8d7f51bc5f54323fc40cbd874119354ab609bef6e4cb`, `8605e365edf11160aad517c7d79a3b26b62290e5072ef97b102a01ddbb343f14`


## Why this matters

Severity classified as **CRIT** based on: IOCs present, 12 use case(s) fired, 17 technique(s) inferred. Read the full article for actor attribution, tooling details, and any defanged IOCs in the body that aren't visible in the RSS summary.