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Update:
Payload C is probably tied to MetaStealer and was recently detailed by Huntress (which named it Potemkin loader).
# Runster
Orange Cyberdefense has been tracking a previously unnamed modular stealer+loader framework we call #Runster, active since at least November 2025.
Two main delivery methods. Two PowerShell "profiles". A related executable with a DGA component, dropping a DLL.
Full thread + IOC list below.
#ThreatIntel #CTI #RUNSTER
> **Update (2026-06-17):** our related "Payload C" is ***likely*** tied to MetaStealer and was recently [detailed](https://www.huntress.com/blog/potemkin-loader-rmmproject-clickfix-attack) by Huntress, which named it **Potemkin loader**. Another blog by Walmart on this new DGA is available [here](https://medium.com/walmartglobaltech/metastealer-traffic-new-dgas-and-analyzing-the-tracker-backdoor-dga-with-ai-96ea63dc7c01).
>
RUNSTER refers to the recurring use of the /run URL path pattern in C2 communication, and to the delicious Munster Alsatian cheese, in line with our cheesy-based naming convention. ---
Our investigation started after @EclecticIQ, building on @g0njxa, and @OntinueMXDR independently documented campaigns with overlapping infrastructure at events.msft23[.]com. Orange Cyberdefense has been tracking a previously unnamed modular stealer-loader framework we call **Runster**, active since at least November 2025. Two main delivery methods. Two PowerShell modules stealing data. A third, related executable with a DGA component dropping a full-featured DLL.
Runster was distributed through two main methods: ![RUNSTER attack chain](runster_attack_chain.png)
*RUNSTER delivery and modular architecture — Orange Cyberdefense*
Trojanized MSI/EXE installers, delivered via the EmEditor supply-chain (Dec 2025), **RUNSTER** refers to the recurring use of the `/run` URL path pattern in C2 communication, and to the delicious Munster Alsatian cheese, in line with our cheese-based naming convention.
SEO poisoning: fake KeePassXC, Mullvad VPN, WinSCP... malicious ads or abusing InstallFix lures (fake Claude Code and Gemini CLI pages)
Two distinct but related PowerShell modules: Our investigation started after EclecticIQ(https://blog.eclecticiq.com/seo-poisoning-campaign-leverages-gemini-and-claude-code-impersonation-to-deliver-infostealer), building on [@g0njxa](https://x.com/g0njxa/status/2041636371790495798/), and [Ontinue](https://www.ontinue.com/resource/blog-behind-a-fake-claude-code-installer/) independently documented campaigns with overlapping infrastructure at `events.msft23[.]com`.
1) Credential-theft payload via /run/<token> ---
Suppresses PowerShell ETW telemetry, bypasses AMSI, and terminates if a virtual machine is detected (qemu-ga) ## Delivery
Browser data and Windows Credential Manager
Slack, Teams, Discord, and Telegram
SSH, OpenVPN, OAuth, CI/CD tokens
Cryptocurrency wallets
2) Browser-based data theft via /gate/start/<token> - **EmEditor supply-chain compromise** (Dec 2025): trojanized MSI served directly from the vendor's download path
- **SEO poisoning and malicious ads**: fake download pages impersonating KeePassXC, Mullvad VPN, WinSCP and others; InstallFix-style lures impersonating Claude Code and Gemini CLI
Geofences CIS countries + Iran ---
Injects a native PE helper into Chromium browsers
uses IElevator2 COM to recover a 32-byte ABE key
Packages everything as secure_prefs.zip → PUT /gate/init/
It also persists through a scheduled task and polls /gate/auto/ for follow-on PowerShell stages. ## Payloads
We also identified a Runster-associated executable with a DGA component through VT telemetry and sandbox analysis. Two DGA variants confirmed: ### Payload A: Credential theft via `/run/<token>`
char-based: [a-z]{16}.xyz (seed 53275) - Suppresses PowerShell ETW telemetry, bypasses AMSI, and terminates if a virtual machine is detected (`qemu-ga`)
wordlist-based: word1-word2-word3.xyz (seed 151678) - Browser data and Windows Credential Manager
- Slack, Teams, Discord and Telegram
- SSH, OpenVPN, OAuth and CI/CD tokens
- Cryptocurrency wallets
C2 flow: /api/client_hello → /avast_update → /api/client/new → /tasks/get_worker → /tasks/collect ### Payload B: Browser-data theft via `/gate/start/<token>`
/avast_update delivers a DLL with capabilities that include browser theft, keylogging, HVNC, SOCKS/backconnect, shell command execution, file theft, screenshots, screen recording, and wallet theft. - Geofences CIS countries and Iran
- Injects a native PE helper into Chromium browsers and uses IElevator2 COM to recover a 32-byte App-Bound Encryption key
- Packages collected data as `secure_prefs.zip` → PUT `/gate/init/`
- Persists through a scheduled task and polls `/gate/auto/` for follow-on PowerShell stages
Evidence that connects the campaigns: ### Payload C: EXE/DGA loader (***likely*** MetaStealer / Potemkin loader)
Recurring C2 path conventions (/run/, /gate/, /api/client_) Two DGA variants confirmed:
Infrastructure overlaps (shared IPs, redirect fingerprint, domain naming patterns)
Code-level similarities
Co-delivery in the EmEditor campaign: both PowerShell variants delivered simultaneously
Assessment: The two PowerShell "profiles" are highly likely part of the same cluster and likely share a source lineage or common toolchain. - Char-based: `[a-z]{16}.xyz` (seed `0xD01B`)
- Wordlist-based: `word1[-]word2[-]word3.xyz` (seed `0x2507E`)
The /gate/* geofencing (CIS + Iran) suggests a possible CIS nexus. We do not attribute RUNSTER to a specific country or known threat actor so far. C2 flow: `/api/client_hello``/avast_update``/api/client/new``/tasks/get_worker``/tasks/collect`
Monitor: ### Payload D: Stealer / task-worker DLL (via `/avast_update`)
PS paths: /run/, /take/, /process/, /validate/, /gate/(start|init|auto)/
Native paths: /api/client_hello, /avast_update, /tasks/*
User-Agent: cpp-httplib/0.12.1
Hunt for: hidden irm|iex, secure_prefs.zip, PT1M scheduled tasks, %LocalAppData%\hyper-v.ver, Add-MpPreference exclusions
Browser theft, keylogging, HVNC, SOCKS/backconnect, shell command execution, file theft, screenshots, screen recording, wallet theft.
We published a full report for our Strategic CTI Advisories' customers last week. Related IoCs are available in our public GitHub repository: https://github.com/cert-orangecyberdefense/cti/blob/main/runster/ ---
Thanks to @TrendMicroHome for the additional details on this cluster. Public reporting by @g0njxa, @EclecticIQ, @OntinueMXDR, @Stormshield, Qianxin, and @ReversingLabs supported this investigation. ## Evidence connecting the campaigns
- Recurring C2 path conventions (`/run/`, `/gate/`, `/api/client_*`)
- Infrastructure overlaps — shared IPs, redirect fingerprint, domain naming patterns
- Code-level similarities across PowerShell samples
- Co-delivery confirmed in the EmEditor campaign: both PowerShell modules delivered simultaneously via RunspacePool
---
## Assessment
The two PowerShell modules are ***highly likely*** part of the same cluster and ***likely*** share a source lineage or common toolchain. The `/gate/*` geofencing covering CIS countries and Iran suggests a possible CIS nexus. We do not attribute Runster to a known threat actor at this time.
---
## Detection
Monitor outbound HTTP(S) requests for:
```
# PowerShell profiles
/run/[A-Za-z0-9]{8}
/(take|process|validate)/[A-Za-z0-9]{8}
/gate/(start|init|auto)/[A-Za-z0-9]{8}
# Loader
/api/client_hello
/api/client/verify
/avast_update
/tasks/get_worker
/tasks/collect
```
On endpoints, hunt for:
- Hidden `irm <host> | iex` execution following installer activity
- `secure_prefs.zip` in temporary paths
- Scheduled tasks launching `conhost --headless powershell` (PT1M)
- `%LocalAppData%\hyper-v.ver`
- `Add-MpPreference` exclusions for unexpected paths
- HTTP User-Agent `cpp-httplib/0.12.1`
---
## Further reading
A full advisory is available to Orange Cyberdefense Strategic CTI customers.
IOC list: [iocs.md](iocs.md)
---
## Acknowledgements
Thanks to Trend Micro for feedback on this cluster.
Public reporting by @g0njxa, EclecticIQ, Ontinue, Stormshield, Qianxin and ReversingLabs contributed to this investigation.
Led by CTI analysts Asma Lansari and Simon Vernin, with reverse engineering by Alexis Bonnefoi.