Cybercriminals try to leave no trace when they break into bank accounts, phones and PCs, but if someone is in your social media and email accounts there could be warning signs.
'White hat' hacker Ash Shatrieh uses techniques similar to real cybercriminals to 'test' cyber defenses and warn people that they are in danger.
Shatrieh, who works as a Threat Intelligence Researcher at F-Secure, told DailyMail.com about the subtle but telltale signs that you've been hacked.
For example, consider seeing different content than you are used to on your timeline, or no longer receiving notifications on your phone as you are used to.
If someone is in your social media and email accounts, there may be warning signs
He said: 'In response to suspicious account activity, you should contact the service provider and reset your password to strong, ideally random letters, numbers and characters.
'In some cases, your device (such as a PC) can even be affected by information-stealing malware. In that case, it is important to run an antivirus scan on your computer.'
These are his signs to look out for:
Ash Shatrieh works as a Threat Intelligence Researcher at F-Secure (F-Secure)
The content you see on social media is changing
If you suddenly see unfamiliar content on social media, or content in new languages, it could be a sign that someone is in your account.
Shatrieh said: “Be alert to changes in the content you see on social media.
“Sudden shifts, such as an influx of messages in unknown languages or suggestions from accounts you haven't interacted with yet, could indicate suspicious activity.
“Social media algorithms are tailored to your preferences, and unexpected changes could indicate unauthorized access.”
You get messages, but no notifications
If you see messages popping up in your account but don't get the usual notifications on your phone, it could be a warning sign that someone else is seeing them first.
The hacker could have set up rules in your inbox to redirect certain messages so they can compromise other accounts, including bank accounts, Shatrieh warned.
Shatrieh said: “Be wary if you notice the presence of new, unread emails without receiving corresponding notifications and experiencing delivery delays.
“This could be an indication that hackers have set up rules that can redirect or hide emails from your inbox, suggesting that the hacker is selectively releasing some messages and hiding others.”
Shatrieh added: “Check your Inbox settings to see if there are any rules that redirect emails to addresses you don't know.”
Very small transactions appear in your online banking
The goal of most hackers is simple: they want to get money, and once they have an email account, they will try to perform actions including compromising bank accounts.
Even small, unrecognized charges (like a few cents) can be a warning sign.
Shatrieh said, “Regularly check bank or credit card statements for unauthorized transactions. Hackers may initiate small transactions as a test before attempting larger transactions.
'Remain vigilant, even with apparently insignificant amounts and report suspicious transactions immediately to your bank. If you see attempts to spend with your card, call your bank and cancel the card.”
A new 'trusted device' appears
Most online services have a list of 'trusted devices'. If you see one that isn't yours, it's a warning sign that something fishy is going on.
Shatrieh said: “Keep an eye on the list of 'trusted devices' or 'logged in devices' from service providers. Unknown devices, especially from remote locations, can signal unauthorized access.
'This information could help identify the potential source of the hack. Again, in Gmail you can do this by checking the activity logs.
'Note that one compromised account does not mean others are compromised; it could be an isolated incident.”
A yellow banner will appear below your email
In Gmail on desktop, you'll see a yellow banner indicating that someone has logged in from an unknown location (below the email window).
Most online services offer activity logs that can help you monitor logins and track hackers.
Shatrieh said: “Regularly check service activity logs to verify login timestamps and IP addresses.
'In Gmail, for example, an unknown location can trigger a yellow banner at the bottom. Investigate unusual activity, revoke unknown sessions (you can also request to log out of all logged-in devices), and immediately secure your account by resetting your credentials. Please note that compromised devices can lead to a compromised account.'
Your account has been suspended
A major warning sign of malicious activity is if your account is suddenly suspended or canceled, Shatrieh said.
Shatrieh said: “Be aware of unexpected account terminations. 'If you receive notifications about account suspensions or terminations, this may indicate malicious activity.
'Contact the service providers immediately to investigate and resolve the issue.
Being suddenly logged out could also be a warning sign, Shatrieh said.
'If you notice that you have been logged out repeatedly without starting, investigate for any suspicious login attempts.
“Review your active sessions, trusted devices, and login device list and if anything seems suspicious, revoke access, change your password, and verify that multi-factor authentication is set up and working properly.”