Safe Attachment Extensions Vs. Risky?

[ProCom]

For the setting: "Allowed attachment file extensions"

For those of us that aren't developers (me ) how do we determine the risk-level of different extensions to allow?

zip ?
csv ?
pdf ?
txt ?
xlxs ?
etc?

How "safe" or "risky" are those (and other) extensions to allow uploads?

I read the interwebs about Malware Infection, Injection Attacks, etc. etc. etc.

I want to support uploads to some extent, but not anything where a hacker could super easily cause problems.

Thanks!
Safe Attachment Extensions Vs. Risky?

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