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There has been a security breach. What should I do?

Attacks against your systems and networks can happen at any time, to any person or business. The effects can be devastating, often crippling productivity and exposing sensitive data.

There are some ways to tell if there was an attack on your systems and network:

  • You notice unusual activity on your systems, network or files, or you cannot access them.
  • Your computer or network is slower than normal.
  • People are receiving suspicious emails that appear to be from you or your company.
  • You have received a ransom to decrypt your data or prevent it from being leaked or sold online.

Not sure how or why it happened?

Learn more about system and network attacks.

Who should I contact?

ASD's ACSC ReportCyber

Report cybercrimes, security incidents and abuse through ReportCyber. Your report helps to disrupt crime operations and makes Australia more secure. If your money and/or identity is at risk, also notify the relevant services below.

More information

Need more support?

For help with all types of threats, visit our where to get help page.

If you still need help, call our hotline 24/7 on 1300 CYBER1 (1300 292 371).

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