Integrity attacks attempt to disrupt trust in the data or the system itself. In an integrity attack on data, a file is accessed without authorization and altered to reflect some information other than what authorized users intend. An example of an integrity attack is someone accessing a system without authorization to change information in a file.
Additionally, an entire system may have its integrity compromised by having unauthorized commands executed on that system. An example might be malware that tells a computer to perform an operation without the authorized user's knowledge, while giving the authorized user feedback that the computer is operating as normal.
These types of attack are illegal under the Computer Fraud and Abuse Act.
- "Overview" section: Cybersecurity: Selected Issues for the 115th Congress, at 3.