Apple Clarifies New Security Alerts in macOS Sequoia 26.4
Apple has published a support document titled "If your Mac blocks a Terminal command paste or script" to explain the new security alerts introduced in macOS Sequoia 26.4.
The alert appears if you do not regularly use Terminal and copied the command from a website, chat agent, or messaging or email app.
The document clarifies when users might see a popup blocking a command paste into Terminal. Specifically, the alert triggers under two key conditions:
- The user does not frequently use the Terminal application.
- The command was copied from an external source, such as a website, chat agent, or a messaging or email app.
Additionally, Apple explains that more severe alerts—such as "Malware Detected, Paste Blocked" or "Malicious Script Blocked" —appear if macOS detects known malware in the command or script. In these cases, there is no option to continue pasting.
When known malware is detected, there is no option to continue pasting.
For users who believe a block was made in error, Apple provides a way to report the issue and have the block reviewed.