Verify an App's Code Signature with codesign

Check whether an application bundle was signed properly and hasn't been modified since.

macOSGatekeepersignaturecodesignsecurityLow risk

Run `codesign --verify --deep --strict --verbose=2 /Applications/App.app`; valid output ends with 'valid on disk' and 'satisfies its Designated Requirement'.

01Command

Command

$ codesign --verify --deep --strict --verbose=2 /Applications/SomeApp.app

02What it does

codesign validates the cryptographic seals inside an app bundle, catching anything from a corrupted download to deliberate malware patching. --deep recurses into nested frameworks and helpers that a shallow check misses, while --strict enforces modern requirements. Add `codesign -dv --entitlements - <app>` to display the Team ID and entitlements like the JIT or audio-driver permission.

03Risk

RiskLow risk

04Undo

✓No undo needed — this command does not change persistent state.

05Sources

macOS codesign — create and manipulate code signatures
SS64 · technical · 2026-09-17
Evidence: Documents codesign --verify, --deep, --strict and --display flags.
Code Signing Guide
Apple Developer · vendor-doc · 2026-09-17
Evidence: Apple explains code signature validation and why deep verification checks nested code.

Last verified: 2026-09-17 · Category: System & Settings

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