EICAR test file

[3] Anti-virus programmers set the EICAR string as a verified virus, similar to other identified signatures.

The test string was written by noted anti-virus researchers Padgett Peterson and Paul Ducklin and engineered to consist of ASCII human-readable characters, easily created using a standard computer keyboard.

[7] It makes use of self-modifying code to work around technical issues that this constraint imposes on the execution of the test string.

As a result, antiviruses are not expected to raise an alarm on some other document containing the test string.

[11] The test file can still be used for some malicious purposes, exploiting the reaction from the antivirus software.