CVE-2026-12581 describes a session fixation vulnerability in Digiwin EasyFlow .NET. The flaw allows an unauthenticated remote attacker to replace a session ID for a user before login. When the user authenticates, the attacker can hijack the session and gain the user's privileges. The vulnerability is categorized under CWE-384 (Session Fixation). The CVSS 4.0 vector indicates network attack vector, low attack complexity, partial attack traceability, no privileges required, user interaction required, and high impacts on confidentiality, integrity, and availability. No official remediation or patch information is currently available.

Successful exploitation allows an attacker to hijack a user's session by fixing the session ID before login, thereby gaining the user's privileges. This can lead to unauthorized access to sensitive information and actions within the EasyFlow .NET application. The high CVSS score reflects significant confidentiality, integrity, and availability impacts.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, users should consider implementing additional session management controls such as regenerating session IDs upon login and monitoring for suspicious session activity if possible.