Analysis and Solutions for Application Permission Issues in macOS Big Sur

Problem Background and Error Analysis

With the release of macOS Big Sur (version 11), many users encountered issues where applications failed to run properly after system upgrades. Typical error messages include "You do not have permission to open the application" or "kLSNoLaunchPermissionErr" error codes in the terminal. These permission issues primarily stem from Big Sur's enhanced security mechanisms, particularly stricter requirements for application signing and binary file verification.

UPX Compressed Binary File Compatibility Issues

A common but often overlooked issue in macOS Big Sur is the inability to properly recognize and execute UPX (Ultimate Packer for eXecutables) compressed binary files. UPX is a popular executable file compression tool, but in Big Sur, the system cannot correctly process these compressed binaries, leading to permission verification failures.

When applications are compressed with UPX, they exhibit the following typical symptoms in Big Sur:

• Graphical interface displays permission denial errors
• Terminal returns error code -10826
• Applications exit abnormally during startup

Solution: UPX Decompression

For permission issues caused by UPX compression, the most effective solution is to decompress the binary files. Here are the detailed steps:

First, you need to install the UPX tool. If not already installed, you can install it via the Homebrew package manager:

brew install upx

After installation, locate the application's binary file path. Typically, the application binary is located at:

/Applications/ApplicationName.app/Contents/MacOS/ApplicationName

Use the following command to decompress the binary file:

sudo upx -d /Applications/ApplicationName.app/Contents/MacOS/ApplicationName

Note that sudo privileges are required to execute this command because application directories are typically protected by the system. After decompression is complete, the application should be able to start normally.

Alternative Solutions

In addition to the UPX decompression method, the following alternative solutions can be attempted:

Re-signing the Application

If UPX decompression doesn't resolve the issue, try re-signing the application:

codesign --force --deep --sign - /Applications/ApplicationName.app

This command forces re-signing of the application and all its components using a temporary identity. This method is particularly suitable for applications with damaged or expired signatures.

Modifying File Permissions

In some cases, file permission settings may be problematic. Permissions can be repaired with the following command:

chmod -R 755 /Applications/ApplicationName.app

This command recursively sets read, write, and execute permissions for the application directory, ensuring the system can properly access application files.

Removing Quarantine Attributes

For applications downloaded from the internet, the system may set quarantine attributes. These can be removed with:

sudo xattr -rd com.apple.quarantine /Applications/ApplicationName.app

Technical Principle Analysis

macOS Big Sur introduced more stringent security mechanisms, including:

• Enhanced Code Signature Verification: The system performs stricter verification of application signatures to ensure code integrity and trusted sources
• Runtime Protection: Strengthened security checks during application execution to prevent malicious code execution
• Binary File Integrity Checking: More rigorous validation of executable file formats and structures

UPX compression alters the structure of binary files, which may cause verification failures under Big Sur's strict validation mechanisms. After decompression restores the original file structure, the system can properly recognize and execute the application.

Preventive Measures and Best Practices

To avoid similar permission issues, the following preventive measures are recommended:

• Update applications to the latest versions promptly to ensure compatibility with the latest macOS system
• Download applications from official sources, avoiding modified or cracked versions
• Regularly check application signature status to ensure signatures are valid
• Back up important data and application configurations before system upgrades

Conclusion

Permission issues in macOS Big Sur primarily stem from enhanced system security mechanisms, particularly compatibility issues with UPX-compressed binary files. Through methods such as UPX decompression, re-signing, and permission repair, most application execution problems can be effectively resolved. Understanding these technical principles and solutions helps users better manage and maintain applications in the macOS system.