How to Detect and Neutralize Telecom Sleeper Cells and AI Jailbreaks

Introduction

This week in cybersecurity, the headlines have been deceptively quiet. While no massive zero-days dominated the cycle, the emergence of "telecom sleeper cells" and the evolution of Large Language Model (LLM) jailbreaks signal a shift toward more insidious, persistent threats. For defenders, this means the battle isn't just about loud explosions—it's about finding the silent, long-running operations that have been burrowing into infrastructure for years.

At Security Arsenal, we emphasize that "quiet" weeks often represent the most dangerous times for organizations. Adversaries are leveraging old attack methods in new places, utilizing valid credentials to move laterally, and exploiting the trust models of modern AI. This post dissects these threats and provides the defensive toolkit you need to hunt them down.

Technical Analysis

Telecom Sleeper Cells and Persistence

The term "sleeper cells" in a telecom context refers to Advanced Persistent Threats (APTs) establishing a foothold within critical infrastructure or service providers, maintaining persistence for extended periods (years) before executing their primary objective, such as data exfiltration or surveillance. These operations often exploit:

• Valid Accounts: Compromised credentials of privileged users.
• Living Off The Land (LotL): Using native tools like PowerShell and WMI to evade detection.
• Supply Chain Compromise: Hijacking trusted update mechanisms.

LLM Jailbreaks and AI Security

Parallel to infrastructure threats is the rise of LLM jailbreaks. Attackers are using prompt injection techniques to bypass safety guardrails of AI models. While this seems like a software issue, the security risk to enterprises is significant:

• Data Leakage: Manipulating AI into revealing sensitive training data or proprietary information.
• Malware Generation: Bypassing filters to generate code for ransomware or phishing campaigns.

Defensive Monitoring

To combat these low-and-slow persistence mechanisms and AI-related risks, security teams must move beyond signature-based detection. We need behavioral analytics and threat hunting.

SIGMA Rules

These rules target common persistence mechanisms used in sleeper cell operations and suspicious interactions indicative of AI abuse attempts.

---
title: Suspicious Windows Service Creation via PowerShell
id: 6ba4a8b8-9c2f-4a3e-8b1a-1c2d3e4f5a6b
status: experimental
description: Detects the creation of new Windows services using PowerShell, a technique often used for persistence by APTs.
references:
  - https://attack.mitre.org/techniques/T1543/003/
author: Security Arsenal
date: 2026/03/28
tags:
  - attack.persistence
  - attack.t1543.003
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith: '\powershell.exe'
    CommandLine|contains: 'New-Service'
  condition: selection
falsepositives:
  - Legitimate administrative software installation
level: medium
---
title: Potential Prompt Injection via CLI Tools
id: a1b2c3d4-e5f6-4a7b-8c9d-0e1f2a3b4c5d
status: experimental
description: Detects suspicious use of command-line tools like curl interacting with known AI endpoints, which may indicate automated jailbreaking or data exfiltration.
references:
  - https://attack.mitre.org/techniques/T1059/003/
author: Security Arsenal
date: 2026/03/28
tags:
  - attack.execution
  - attack.t1059.003
logsource:
  category: process_creation
  product: windows
detection:
  selection:
    Image|endswith:
      - '\curl.exe'
      - '\powershell.exe'
    CommandLine|contains:
      - 'api.openai.com'
      - 'generativelanguage.googleapis.com'
    CommandLine|contains:
      - 'jailbreak'
      - 'ignore instructions'
      - 'developer mode'
  condition: selection
falsepositives:
  - Authorized testing of AI integrations by developers
level: high

KQL Queries

Use these queries in Microsoft Sentinel or Defender for endpoint investigation.

// Hunt for new service creation events
DeviceProcessEvents
| where Timestamp > ago(7d)
| where FolderPath endswith "\\powershell.exe" 
| where ProcessCommandLine contains "New-Service"
| project Timestamp, DeviceName, AccountName, ProcessCommandLine, InitiatingProcessFileName
| order by Timestamp desc

// Investigate potential AI API abuse
DeviceNetworkEvents
| where Timestamp > ago(24h)
| where RemoteUrl has "api.openai.com" or RemoteUrl has "generativelanguage.googleapis.com"
| where InitiatingProcessFileName in ("curl.exe", "powershell.exe", "cmd.exe")
| project Timestamp, DeviceName, InitiatingProcessAccountName, RemoteUrl, RequestUrl, BytesSent

Velociraptor VQL

Hunt for persistence mechanisms on the endpoint using Velociraptor.

-- Hunt for recently created services that are not signed by Microsoft
SELECT Name, DisplayName, State, StartType, PathName, ProcessId
FROM win_service_list()
WHERE State = 'Running'
  AND StartType = 'Auto'
  AND NOT PathName =~ 'C:\\Windows\\System32\\svchost.exe'
  AND NOT PathName =~ '"C:\\Program Files'
  AND NOT PathName =~ '"C:\\Program Files (x86)'

-- Hunt for PowerShell scripts containing suspicious API calls
SELECT FullPath, Mtime, Size
FROM glob(globs='C:\\Users\\*\\*.ps1')
WHERE read_file(filename=FullPath) =~ 'api.openai.com'
   OR read_file(filename=FullPath) =~ 'Invoke-WebRequest'

PowerShell Verification Script

Run this script to audit for suspicious services or scheduled tasks commonly used in sleeper cell operations.

# Audit for non-Microsoft services set to Auto Start
Get-WmiObject Win32_Service | 
Where-Object { 
    $_.StartMode -eq 'Auto' -and 
    $_.State -eq 'Running' -and 
    $_.PathName -notmatch 'C:\Windows\System32\' -and
    $_.PathName -notmatch '"C:\Program Files' 
} | 
Select-Object Name, DisplayName, PathName, StartName | 
Format-Table -AutoSize

# Check for suspicious Scheduled Tasks
Get-ScheduledTask | 
Where-Object { 
    $_.State -eq 'Ready' -and 
    $_.TaskPath -notmatch '\\Microsoft\\' 
} | 
Select-Object TaskName, TaskPath, Actions | 
Format-List

Remediation

To protect your organization against these persistent and emerging threats:

1. Implement Least Privilege: Revoke unnecessary administrative rights. Telecom sleeper cells thrive on over-privileged accounts.
2. Zero Trust Architecture: Assume breach. Validate every request, regardless of its origin (internal or external).
3. AI Governance Policies: Establish strict policies on how LLMs can be accessed within the network. Use enterprise-managed instances of AI tools rather than public web interfaces where possible.
4. Patch and Configuration Hardening: Ensure all systems are up to date. Disable unused services and protocols (e.g., PowerShell Remoting) where not required.
5. Audit Log Retention: Ensure logs are retained for at least 6-12 months. Long-running operations are often only discovered during historical forensic analysis.

Executive Takeaways

The landscape is shifting from noisy ransomware to quiet, espionage-focused operations. The convergence of infrastructure persistence and AI abuse requires a defense-in-depth strategy. IT leaders must prioritize visibility into service creation and AI usage patterns to detect these "sleeper" threats before they activate.

Related Resources

Security Arsenal Alert Triage Automation AlertMonitor Platform Book a SOC Assessment platform Intel Hub