How to Detect a Java JAR Supply Chain Attack

How malicious code gets smuggled into legitimate-looking JAR dependencies, and how to catch it with static analysis before it reaches your build — using a free online scanner.

What a JAR Supply Chain Attack Looks Like

Step 1: Treat Every New or Updated Dependency as Untrusted

Step 2: Run an Automated Behavioral Scan

Step 3: Read the Findings in Context, Not Just the Verdict

Step 4: Decompile and Read the Specific Flagged Classes

Step 5: Diff Behavior Against the Previous Version

Step 6: Automate the Check in CI

What This Catches and What It Doesn't

Summary