900+ Sangoma FreePBX Instances Compromised in Ongoing Web Shell Attacks  Ravie Lakshmanan  Feb 27, 2026 Network Security / Vulnerability The Shadowserver Foundation has revealed that over 900 Sangoma FreePBX instances still remain infected with web shells as part of attacks that exploited a command injection vulnerability starting in December 2025. Of these, 401 instances are located in the U.S., followed by 51 in Brazil, 43 in Canada, 40 in Germany, and 36 in France. The non-profit entity said the compromises are likely accomplished via the exploitation of CVE-2025-64328 (CVSS score: 8.6), a high-severity security flaw that could enable post-authentication command injection. "The impact is that any user with access to the FreePBX Administration panel could leverage this vulnerability to execute arbitrary shell commands on the underlying host," FreePBX said in an advisory for the flaw in November 2025. "An attacker could leverage this to obtain remote access to the system as the asterisk user." The vulnerability affects FreePBX versions higher than and including 17.0.2.36. It was resolved in version 17.0.3. As mitigations, it's advised to add security controls to ensure that only authorized users have access to the FreePBX Administrator Control Panel (ACP), restrict access from hostile networks to the ACP, and update the filestore module to the latest version. The vulnerability has since come under active exploitation in the wild, prompting the U.S. Cybersecurity and Infrastructure Security Agency (CISA) to add it to its Known Exploited Vulnerabilities (KEV) catalog earlier this month. Source: The Shadowserver Foundation In a report published late last month, Fortinet FortiGuard Labs revealed that the threat actor behind the cyber fraud operation codenamed INJ3CTOR3 has been exploiting CVE-2025-64328 starting early December 2025 to deliver a web shell codenamed EncystPHP. "By leveraging Elastix and FreePBX administrative contexts, the web shell operates with elevated privileges, enabling arbitrary command execution on the compromised host and initiating outbound call activity through the PBX environment," the cybersecurity company noted. FreePBX users are recommended to update their FreePBX deployments to the latest version as soon as possible to counter active threats. Found this article interesting? Follow us on Google News , Twitter and LinkedIn to read more exclusive content we post. SHARE      Tweet  Share  Share  Share   Share on Facebook  Share on Twitter  Share on Linkedin  Share on Reddit  Share on Hacker News  Share on Email  Share on WhatsApp Share on Facebook Messenger  Share on Telegram SHARE  CISA , Command Injection , cybersecurity , FreePBX , network security , Patch Management , Vulnerability , Web Shell Trending News Researchers Show Copilot and Grok Can Be Abused as Malware C2 Proxies ⚡ Weekly Recap: Double-Tap Skimmers, PromptSpy AI, 30Tbps DDoS, Docker Malware and More ThreatsDay Bulletin: Kali Linux + Claude, Chrome Crash Traps, WinRAR Flaws, LockBit and 15+ Stories Cisco SD-WAN Zero-Day CVE-2026-20127 Exploited Since 2023 for Admin Access Claude Code Flaws Allow Remote Code Execution and API Key Exfiltration Anthropic Says Chinese AI Firms Used 16 Million Claude Queries to Copy Model Anthropic Launches Claude Code Security for AI-Powered Vulnerability Scanning AI-Assisted Threat Actor Compromises 600+ FortiGate Devices in 55 Countries ClickFix Campaign Abuses Compromised Sites to Deploy MIMICRAT Malware Cline CLI 2.3.0 Supply Chain Attack Installed OpenClaw on Developer Systems PromptSpy Android Malware Abuses Gemini AI to Automate Recent-Apps Persistence Notepad++ Fixes Hijacked Update Mechanism Used to Deliver Targeted Malware Dell RecoverPoint for VMs Zero-Day CVE-2026-22769 Exploited Since Mid-2024 Citizen Lab Finds Cellebrite Tool Used on Kenyan Activist’s Phone in Police Custody Identity Prioritization isn't a Backlog Problem - It's a Risk Math Problem How Exposed Endpoints Increase Risk Across LLM Infrastructure Popular Resources 100+ Domains Multiply Attack Risk 6× - Download the CTEM Divide Research Boost SOC Efficiency with AI-Guided Triage — Download Investigator Overview Silent Residency Is the New Threat Model — Download the Red Report Exposed Cloud Training Apps Are Letting Hackers In — Download the Research