One of my customers had a problem making a post at his blog, and when I looked into the database I found out that the newsletter table (which sends emails about the blog posts) had a malicious script.
Since I'm just a rookie front-end developer, I have no clue about what would this script do. Could anyone help me with the goal of the attacker?
Also, while looking at the ip of the attacker (which was not obfuscated) I could find that he was using a university to make it. (Not really far from where I am and my customer's location)
I'm using a client validation and also validating the data in my back-end with regex. And this script does not match the parameters, so, I suspect he made a post to the db.
How can I prevent this kind of attack?
And what did the attacker wanted?
As requested, the code:
firstname.lastname@example.org email@example.com' and 2*3*8=6*8 and 'sfn7'='sfn7 firstname.lastname@example.org" and 2*3*8=6*8 and "sxju"="sxju email@example.com%' and 2*3*8=6*8 and 'l6b4'!='l6b4% firstname.lastname@example.org&n945604=v918673 email@example.com'"()&%<acx><script >j9ml(9550)</script> firstname.lastname@example.org_9225
Sorry if this is not the place to make this question, I thought it might not be a StackOverFlow question.