What's Your Sign? Application Overview

Overview

What's Your Sign? is a macOS system utility designed to allow users to easily and intuitively view the code signing information of any file. This tool integrates directly into macOS Finder by adding a right-click context menu option, bringing critical security information—previously accessible only via command line—into a familiar graphical interface.

Core Value: It empowers users to quickly assess the trustworthiness and origin of applications or files, serving as an effective tool to enhance macOS security awareness and defend against malware.

Key Features & Highlights

1. Seamless Integration with Finder Right-Click Menu

• After installation, right-click (or Control-click) on any file in Finder to reveal the new “Code Signing Info” menu item.
• No need to open a separate application—querying signature information becomes part of the natural file browsing workflow.

2. Clear and Intuitive Signature Information Display

Clicking the menu opens an information window displaying detailed code signing status, including:

• Signer Identity: Clearly shows the certificate holder, such as Software Signing (Apple official) or third-party developers (e.g., Developer ID Application: Objective-See (XYZ123ABC)).
• Expiration Date: Displays the certificate’s validity period.
• Entitlements: Shows code signing entitlements, such as com.apple.private.* for Apple-signed files with special permissions.
• Digest Algorithm: E.g., SHA-256.
• Timestamp: The timestamp from the signing server, used to verify the signing time.

3. Visual Trust Level Indicators

Uses color-coded lock icons to instantly convey trustworthiness at a glance:

• Green Lock: Signed by Apple (e.g., system apps). Represents the highest level of system trust.
• Black Lock: Signed by a valid Apple Developer ID, typically notarized. Common for legitimate third-party apps trusted by Gatekeeper.
• Red Open Lock: File is unsigned, or its certificate is expired or revoked. A security warning indicating potential risk, often seen with malware or pirated software.

4. Broad Compatibility

• Supports macOS 10.13 (High Sierra) and all later versions.
• Can detect and analyze code signing status for any file type (applications, scripts, plugins, libraries, etc.).

Advantages

1. Enhanced Security Transparency and User Empowerment

• Simplifies Complexity: Transforms complex terminal commands like codesign or pkgutil into a single click, making critical security metadata accessible to non-technical users.
• Proactive Verification: Enables users to verify an application’s signature before running it, allowing them to assess reliability beyond relying solely on Gatekeeper’s automatic blocking.

2. Assists in Malware Detection

• Many malware samples use invalid, forged, or revoked certificates, or go unsigned entirely to bypass system protections. The red warning icon in What’s Your Sign? quickly flags such issues.
• As a tool developed by Objective-See, it’s built with security research and malware analysis in mind, ensuring professional-grade reliability.

3. Lightweight and Free & Open Source

• Extremely lightweight, running as a Finder extension without consuming significant system resources.
• Completely free and its source code is publicly available on GitHub (project name: WhatsYourSign). This ensures transparency and security, allowing security experts to audit the code.

4. Developed by Renowned Security Experts

• Created by Patrick Wardle and his team at Objective-See, renowned security researchers specializing in macOS. The team has developed widely respected security tools like BlockBlock, RansomWhere?, and DoNotDisturb, enjoying strong credibility in the security community.

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Target Users:

• Regular macOS users concerned about digital security and wanting to understand the origin of their software.
• System administrators and IT support staff for quickly verifying software compliance in enterprise environments.
• Security researchers, journalists, or professionals needing to validate file authenticity and integrity.

Summary: What’s Your Sign? is a well-designed, purpose-driven utility that bridges a gap in macOS’s native interface by visualizing code signing information. With its minimalist approach, it grants users a “key” to verify software trustworthiness—making it an essential tool for enhancing security awareness and proactive defense.