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(also frohoff, YSoSerial,

Ysoserial definition

Ysoserial is a programming tool that can be used to exploit Java deserialization vulnerabilities. It consists of modules known as playloads. These playloads generate a serialized object that invokes some action when instantiated, compromising the system or its data.

How can Ysoserial be used to compromise data?

  • Access unauthorized resources
  • Execute malicious code on targeted servers
  • Upload malicious files

How to spot and prevent insecure data deserialization with Ysoserial

  • Implement integrity checks (e.g., digital signatures) to prevent data tampering.
  • Enforce strict type constraints during deserialization.
  • Restrict and monitor incoming and outgoing network connectivity from servers that deserialize.
  • Log deserialization exceptions and failures.