Mac Infostealers on the Rise: What to Know

The days when macOS felt broadly immune to the most common forms of malware are fading. Researchers at Sophos have recently uncovered three distinct campaigns that specifically target macOS users with infostealers — a class of malware that quietly harvests credentials, cookies and other sensitive data.

These campaigns vary in delivery method and sophistication, but share a focus on evasion and data extraction. Some rely on social engineering to trick users into opening malicious attachments or dropping installer packages. Others exploit weakly configured third-party tooling or use signed binaries to appear legitimate to the operating system.

Infostealers are especially concerning because they don’t always announce themselves with obvious symptoms. Instead, they quietly collect passwords stored in browsers, session tokens and sometimes even keychain items, then exfiltrate that information to remote servers. The result can be account takeover, corporate credential theft or broader identity compromise.

So what can mac users do? Start with the basics: keep macOS and all apps updated, enable system and app-level protections, and be cautious about opening unexpected attachments or running downloaded installers. Use reputable antivirus or endpoint protection that includes macOS-targeted threat detection, and enable multi-factor authentication (MFA) on accounts wherever possible to limit damage if credentials are stolen.

Developers and IT teams should also review software signing practices, limit use of unnecessary third-party extensions, and monitor outbound traffic for signs of data exfiltration. For anyone handling sensitive work data on macOS, consider using dedicated browsers or profiles for high-value accounts and a password manager with strong security practices.

While Macs still enjoy strong security foundations, the uptick in infostealer activity is a reminder that no platform is invulnerable. Staying informed and applying layered protections will reduce the chances of becoming a target.