The EICAR test file is a computer file that was developed to test the response of computer antivirus (AV) programs. 😏

X5O!P%@AP[4\PZX54(P^)7CC)7}$EICAR-STANDARD-ANTIVIRUS-TEST-FILE!$H+H*

Similarly for email spam detection (GTUB - Generic Test for Unsolicited Bulk Email) :

XJS*C4JDBQADN1.NSBN3*2IDNEN*GTUBE-STANDARD-ANTI-UBE-TEST-EMAIL*C.34X

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