Silent Replacement of Trusted macOS App Executables

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Affected Platforms#

macOS Tahoe 26.0.0 – 26.5.2

macOS Golden Gate 27 beta 1, 2, 3, and 4

Earlier versions of macOS are likely affected as well, but have not been tested.

macOS provides several safeguards to prevent applications and scripts from tampering with other installed applications. In this post, we show a bug in macOS that allows an attacker to:

Silently replace an application’s main executable under /Contents/MacOS/ without triggering an authorization prompt.

without triggering an authorization prompt. Relaunch the modified application normally, without displaying any security warnings.

Impersonate the trusted application in system permission prompts to request access to Keychain secrets and files protected by Transparency, Consent, and Control (TCC), including those inside ~/Desktop and ~/Documents .

The attack requires only code execution as the current user, and does not require elevated privileges.

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