A malicious advertising campaign targeted users seeking help installing Claude Code by placing Google Ads that appeared to reference the legitimate claude.ai domain and directing victims to attacker-crafted Claude Share pages posing as installation instructions. Researchers reported that the fake guide impersonated Apple support and Claude-related setup content, then pushed victims to run a terminal command whose real payload was obscured with Base64 encoding and shell substitution to hide the download source.
The decoded command reportedly fetched the MacSync infostealer from attacker-controlled infrastructure and used curl with certificate validation disabled, leading to compromise of macOS Keychain contents, browser passwords, session cookies, SSH keys, cloud and developer credentials, Telegram Desktop sessions, and cryptocurrency wallet data. MacSync also established persistence through a LaunchAgent disguised as a Google Keystone updater and could tamper with Ledger Live; responders said any host that executed the command should be treated as fully compromised, isolated, reimaged, and followed by credential rotation, session revocation, and wallet migration.

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Deriv AI reported a malicious Google Ads campaign targeting users searching for Claude Code installation help. The campaign used sponsored ads and Claude share pages disguised as installation instructions to trick macOS users into running a terminal command that installed the MacSync infostealer.
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