• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Microsoft and Cloudflare teamed up to dismantle the RaccoonO365 phishing service

 | 

DoJ resentenced former BreachForums admin to three years in prison

 | 

Apple backports fix for actively exploited CVE-2025-43300

 | 

New supply chain attack hits npm registry, compromising 40+ packages

 | 

Cybercrime group accessed Google Law Enforcement Request System (LERS)

 | 

China-linked Mustang Panda deploys advanced SnakeDisk USB worm

 | 

Insider breach at FinWise Bank exposes data of 689,000 AFF customers

 | 

Hackers steal millions of Gucci, Balenciaga, and Alexander McQueen customer records

 | 

Fairmont Federal Credit Union 2023 data breach impacted 187K people

 | 

UK ICO finds students behind majority of school data breaches

 | 

INC ransom group claimed the breach of Panama’s Ministry of Economy and Finance

 | 

SECURITY AFFAIRS MALWARE NEWSLETTER ROUND 62

 | 

Security Affairs newsletter Round 541 by Pierluigi Paganini – INTERNATIONAL EDITION

 | 

ShinyHunters Attack National Credit Information Center of Vietnam

 | 

FBI warns of Salesforce attacks by UNC6040 and UNC6395 groups

 | 

HybridPetya ransomware bypasses UEFI Secure Boot echoing Petya/NotPetya

 | 

Cisco fixes high-severity IOS XR flaws enabling image bypass and DoS

 | 

Samsung fixed actively exploited zero-day

 | 

UK train operator LNER (London North Eastern Railway) discloses a data breach

 | 

U.S. CISA adds Dassault Systèmes DELMIA Apriso flaw to its Known Exploited Vulnerabilities catalog

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Cyber Crime
  • Malware
  • ESXi ransomware attacks use SSH tunnels to avoid detection

ESXi ransomware attacks use SSH tunnels to avoid detection

Pierluigi Paganini January 27, 2025

Threat actors behind ESXi ransomware attacks target virtualized environments using SSH tunneling to avoid detection.

Researchers at cybersecurity firm Sygnia warn that threat actors behind ESXi ransomware attacks target virtualized environments using SSH tunneling to avoid detection.

Ransomware groups are exploiting unmonitored ESXi appliances to persist and access corporate networks. They use “living-off-the-land” techniques, leveraging native tools like SSH to create undetected SOCKS tunnels for communication with C2 servers.

The researcher reported that in many cases, attackers compromised the ESXi appliances either by using administrative credentials or by exploiting a known vulnerability to bypass the authentication. 

Once gained access to the device, attackers set up the tunneling using the native SSH functionality or by deploying other common tools with similar capabilities.

ESXi appliances’ resilience makes them ideal for tunneling, providing a semi-persistent backdoor within the network.

ESXi ransomware attacks

ESXi appliances splits logs into multiple files by activity, complicating forensic investigations and monitoring activities. Configuring log forwarding is essential to streamline monitoring and centralize event capture.

“While ESXi does support a few third-party monitoring or telemetry agents, such tools are limited in availability. As a more comprehensive and cost-effective solution, configuring syslog forwarding from the ESXi server to an external syslog server can solve the issue. This setup enables centralized monitoring of all activities within the ESXi server and serves as a means of log retention.” reads the Sygnia report.

“The following key log files are the most important ESXi telemetry files that will often assist with detecting and investigating an attack using SSH tunneling techniques on the appliance: 

  • /var/log/vobd.log (VMware observer daemon log) “
  • /var/log/shell.log (ESXi shell activity log) 
  • /var/log/hostd.log (Host agent log) 
  • /var/log/auth.log (authentication log) “

The report provided multiple examples of common activities and messages found in ESXi syslog files  that might be associated to malicious activity. 

Follow me on Twitter: @securityaffairs and Facebook and Mastodon

Pierluigi Paganini

(SecurityAffairs – hacking, ESXi ransomware attacks)


facebook linkedin twitter

Cybercrime ESXI ESXi ransomware attacks Hacking hacking news information security news IT Information Security malware Pierluigi Paganini ransomware Security Affairs Security News

you might also like

Pierluigi Paganini September 17, 2025
Microsoft and Cloudflare teamed up to dismantle the RaccoonO365 phishing service
Read more
Pierluigi Paganini September 17, 2025
DoJ resentenced former BreachForums admin to three years in prison
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Microsoft and Cloudflare teamed up to dismantle the RaccoonO365 phishing service

    Cyber Crime / September 17, 2025

    DoJ resentenced former BreachForums admin to three years in prison

    Cyber Crime / September 17, 2025

    Apple backports fix for actively exploited CVE-2025-43300

    Security / September 17, 2025

    New supply chain attack hits npm registry, compromising 40+ packages

    Malware / September 16, 2025

    Cybercrime group accessed Google Law Enforcement Request System (LERS)

    Security / September 16, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT