diff --git a/scripts/setup/macos/install_cbmc.sh b/scripts/setup/macos/install_cbmc.sh
index 6cd65dac1ac9..2f07a4102d7c 100755
--- a/scripts/setup/macos/install_cbmc.sh
+++ b/scripts/setup/macos/install_cbmc.sh
@@ -14,5 +14,7 @@ fi
 
 # Install CBMC for macOS from CBMC tap
 # https://github.com/diffblue/cbmc/blob/develop/doc/ADR/homebrew_tap.md
+# Homebrew 6.0+ requires explicit trust for third-party taps
+brew trust diffblue/cbmc 2>/dev/null || true
 brew tap diffblue/cbmc
 brew install --overwrite diffblue/cbmc/cbmc@${CBMC_VERSION}