Smishing is the use of text messages to obtain sensitive information or to impersonate a known source.
You've probably received these types of messages before.
Not only are smishing messages annoying to receive, they're also difficult to prevent. That's why some attackers send them.
Some smishing messages are easy to detect.
They might show signs of being malicious like promising a cash reward for clicking an attached link that shouldn't be clicked.
Other times, smishing is hard to spot.
Attackers sometimes use local area codes to appear legitimate.
Some hackers can even send messages disguised as friends and families of their target to fool them into disclosing sensitive information.