Description

EasyFlow .NET developed by Digiwin has an Arbitrary File Upload vulnerability. Privileged remote attackers can upload and execute web shell backdoors, thereby enabling arbitrary code execution on the server.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "7.2",
  "pubDate": "2026-09-30T09:17:13.170Z",
  "pubdate": "2026-09-30T09:17:13.170Z",
  "executiveSummary": "EasyFlow .NET, developed by Digiwin, is susceptible to an Arbitrary File Upload vulnerability.\nThis vulnerability allows a privileged remote attacker to bypass file validation mechanisms and upload malicious files directly to the web server.\nThe primary impact is the potential for Remote Code Execution (RCE) via the execution of uploaded web shell backdoors, granting the attacker full control over the application environment.\nThe vulnerability poses a critical risk to the confidentiality, integrity, and availability of the server and any data managed by the system.\nExploitation requires the attacker to possess authenticated, privileged access to the application’s administrative or file-handling interfaces.\nSuccessful exploitation facilitates unauthorized system commands, data exfiltration, and persistent access to the network infrastructure.",
  "technicalDetails": "The vulnerability originates from inadequate server-side validation of user-supplied files within the EasyFlow .NET application.\nSpecifically, the application fails to restrict the types of files that can be uploaded via its designated upload interfaces, allowing for the submission of executable scripts or binaries.\nThe attack flow commences with the attacker authenticated as a privileged user navigating to the vulnerable upload module within the Digiwin EasyFlow .NET interface.\nThe attacker sends a crafted HTTP POST request containing a malicious payload, typically a web shell (such as an .aspx file), disguised as an authorized document or image.\nBecause the server-side implementation lacks strict extension filtering or MIME-type verification, the malicious file is written to a web-accessible directory.\nOnce the file is successfully placed on the server, the attacker can trigger its execution by sending an HTTP request directly to the path where the file was stored (e.g., /uploads/shell.aspx).\nUpon execution by the .NET runtime, the web shell grants the attacker an interactive command shell with the permissions of the web service account (e.g., IIS_IUSRS).\nThis elevated context allows the attacker to interact with the underlying operating system, move laterally within the network, or deploy further post-exploitation payloads.\nThe lack of integrity checks on file metadata and the absence of restricted file-system permissions for upload directories contribute to the feasibility of this attack.\nThe persistence of the threat is maintained through the continued existence of the backdoored file on the server, even if the session used for the initial upload is terminated."
}