Threat Actors Use CVE-2019-18935 to Deliver Reverse Shells and JuicyPotatoNG Privilege …

Threat Actors Use CVE-2019-18935 to Deliver Reverse Shells and JuicyPotatoNG Privilege …
In early January 2025, eSentire’s Threat Response Unit (TRU) identified a threat actor exploiting the CVE-2019-18935 vulnerability in Progress Telerik UI for ASP.NET AJAX. The attack involved using a reverse shell to execute commands for reconnaissance. The incident emphasizes the importance of patching vulnerabilities, even those that are years old. Affected: Progress Telerik UI for ASP.NET AJAX

Keypoints :

  • eSentire operates 24/7 Security Operations Centers (SOCs) with elite threat hunters and cyber analysts.
  • TRU provides summaries of threat investigations, including responses and future recommendations.
  • The CVE-2019-18935 vulnerability in Progress Telerik UI for ASP.NET AJAX was exploited by an unknown threat actor.
  • Threat actors used w3wp.exe to load a reverse shell and execute reconnaissance commands through cmd.exe.
  • Reverse shells were dropped in the C:WindowsTemp directory with specific naming conventions.
  • eSentire’s SOC team isolated the affected host to contain the infection promptly.
  • Recommendations include the importance of patching systems exposed to the internet.

MITRE Techniques :

  • T1071.001 – Application Layer Protocol: Application Layer Protocol: The threat actor used HTTP to communicate with the C2 server.
  • T1203 – Exploitation for Client Execution: The exploitation of CVE-2019-18935 allowed the threat actor to execute commands remotely.
  • T1059.003 – Command and Scripting Interpreter: The threat actor utilized cmd.exe for executing reconnaissance commands.
  • T1203 – Exploitation of a vulnerability in Progress Telerik UI for ASP.NET AJAX.

Indicator of Compromise :

  • [file name] C:UsersPublicPingCaler.exe
  • [file name] C:UsersPublicJuicyPotatoNG.exe
  • [file name] C:UsersPublicrdp.bat
  • [file name] C:UsersPublicuser.bat
  • [file name] C:UsersPublicAll.bat
  • Check the article for all found IoCs.


Full Research: https://www.esentire.com/blog/threat-actors-use-cve-2019-18935-to-deliver-reverse-shells-and-juicypotatong-privilege-escalation-tool