CVE-2026-102455 Overview
CVE-2026-102455 is an insecure deserialization vulnerability in Digiwin EasyFlow .NET. Unauthenticated remote attackers can execute arbitrary code on the server by sending maliciously crafted serialized content. The flaw is tracked under CWE-502: Deserialization of Untrusted Data and requires no authentication or user interaction. Digiwin EasyFlow .NET is a workflow platform widely deployed in enterprise environments across the Asia-Pacific region. The vulnerability was published by TW-CERT.
Critical Impact
Unauthenticated attackers can achieve remote code execution on the underlying server, compromising confidentiality, integrity, and availability of the application and hosted workflow data.
Affected Products
- Digiwin EasyFlow .NET
Discovery Timeline
- 2026-09-30 - CVE-2026-102455 published to NVD
- 2026-09-30 - Last updated in NVD database
Technical Details for CVE-2026-102455
Vulnerability Analysis
The vulnerability originates in how EasyFlow .NET processes serialized objects supplied over the network. The application deserializes attacker-controlled data without validating its type or origin. During deserialization, .NET reconstructs objects and invokes callbacks such as constructors, property setters, and IDeserializationCallback.OnDeserialization. Crafted gadget chains abuse these callbacks to invoke arbitrary methods on the target system.
Because the endpoint accepting the serialized payload does not require authentication, any network-reachable attacker can trigger the sink. Successful exploitation results in code execution under the identity of the EasyFlow .NET process, typically enabling command execution, credential theft, and lateral movement.
Root Cause
The root cause is the use of an unsafe .NET deserializer such as BinaryFormatter, SoapFormatter, NetDataContractSerializer, LosFormatter, or ObjectStateFormatter on untrusted input. These formatters instantiate arbitrary types identified in the payload and invoke type-specific logic, permitting well-documented gadget chains available in tooling such as ysoserial.net to reach an RCE sink.
Attack Vector
Exploitation is remote and network-based. An attacker submits a serialized object to an exposed EasyFlow .NET endpoint, for example a web service handler or workflow API. The payload embeds a gadget chain that executes an operating system command when the server reconstructs the object graph. No credentials or user interaction are required, and exploitation can be scripted for internet-facing installations. Refer to the TW-CERT Security Advisory and the TW-CERT Incident Report for vendor-published details.
Stop Remote Code Execution Before It Runs
Singularity™ Endpoint detects and blocks exploit attempts at machine speed, including zero-days and novel attack techniques.
Stop Exploit AttemptsDetection Methods for CVE-2026-102455
Indicators of Compromise
- Unexpected child processes spawned by the EasyFlow .NET application pool or worker process, especially cmd.exe, powershell.exe, certutil.exe, or rundll32.exe.
- Inbound HTTP or TCP requests to EasyFlow endpoints containing base64-encoded blobs with markers such as AAEAAAD///// that indicate a BinaryFormatter payload.
- Outbound network connections from the EasyFlow host to unfamiliar external addresses following payload submission.
Detection Strategies
- Inspect web server and application logs for large POST bodies to EasyFlow handlers containing serialized .NET type headers.
- Alert on the EasyFlow process loading unusual assemblies or invoking process creation APIs outside normal workflow execution.
- Correlate deserialization exceptions in application logs with subsequent process or network anomalies on the same host.
Monitoring Recommendations
- Enable Windows process creation auditing (Event ID 4688) with command-line logging on servers hosting EasyFlow .NET.
- Forward IIS or Kestrel access logs to a centralized SIEM and hunt for serialized payload signatures.
- Monitor egress traffic from application servers and flag connections to newly observed domains or IP addresses.
How to Mitigate CVE-2026-102455
Immediate Actions Required
- Restrict network access to EasyFlow .NET endpoints so that only trusted internal clients can reach the affected services.
- Apply the vendor-supplied patch or update as soon as Digiwin publishes remediation guidance through TW-CERT.
- Review authentication logs and process telemetry for signs of prior exploitation before applying the patch.
Patch Information
At the time of publication, refer to the TW-CERT Security Advisory for the current list of fixed versions and vendor patches. Contact Digiwin directly to obtain the updated EasyFlow .NET build addressing CVE-2026-102455.
Workarounds
- Place EasyFlow .NET behind a web application firewall configured to block requests containing serialized .NET object markers.
- Enforce network segmentation and require VPN or reverse-proxy authentication in front of EasyFlow endpoints.
- Disable or remove any EasyFlow modules that accept serialized input over the network if they are not required for business operations.
# Example WAF rule fragment to block common BinaryFormatter payload markers
# Adjust to your WAF syntax and test in detection mode first
SecRule REQUEST_BODY "@rx AAEAAAD/////" \
"id:1026102455,phase:2,deny,status:403,\
msg:'Blocked possible .NET BinaryFormatter payload (CVE-2026-102455)'"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
