Mac malware doesn't need a security flaw when users do the work

Bitdefender's latest Mac threat report shows adware gaining ground as attackers increasingly use browser scams to trick users into bypassing Apple's security protections.

Bitdefender's September 2026 macOS Threat Landscape Report analyzes more than 1.5 billion security events collected between August 2025 and July 2026. Excluding web and document threats, adware rose from 22.6% of detections in the report to 34.4%.

Trojans remained the largest category at 45.2%, down from 51.8%. Potentially unwanted apps also fell from 25.3% to 20.4%.

The shift reflects the growing prominence of malicious ads , browser redirects, and deceptive software installers that trick users into compromising their Macs.

Web and document threats accounted for approximately 45% of the broader detection dataset. Including those detections brings the of Trojans to 24.8%, adware to 18.9%, and potentially unwanted apps to 11.2%.

The figures reflect threats detected by Bitdefender's security products, not confirmed infections across the Mac population. They show how the composition of detected threats has changed, but they don't establish that more Macs are being compromised.

Mac malware increasingly relies on convincing the user

One technique highlighted in the report is ClickFix , which disguises malicious instructions as routine troubleshooting or verification steps. A website might display a fake CAPTCHA, claim that a browser needs an update, or report a technical problem before telling someone to open Terminal and paste a command.

The command can download and execute malware under the user's account. Because the attack begins with a command the user runs, it can avoid some of the security checks that macOS normally applies to downloaded apps.

The technique has also become harder for security researchers to investigate. In August 2026, Microsoft documented a ClickFix campaign involving more than 250 domains that distributed information stealers such as MacSync and Atomic Stealer.

The attackers used browser fingerprinting to identify visitors who appeared to be using genuine Macs. Automated scanners and other visitors could receive harmless-looking pages instead of the malicious instructions, making the campaign more difficult to detect.

ClickFix campaigns can deliver information stealers, which remain a serious threat despite accounting for a relatively small of detections. Bitdefender found that stealer-class detections increased from roughly 0.9% to 1.5% of monthly Mac reports between mid-2025 and mid-2026.

Information stealers can target saved browser credentials, session cookies , cryptocurrency wallets, and macOS Keychain data. Bitdefender couldn't reliably separate ClickFix activity from other detections, however, so the report doesn't establish how much of the stealer activity came from that technique.

Apple's macOS security protections have limits

The report also highlights malware that passed Apple's notarization process , which checks apps for known threats before they're distributed outside the Mac App Store .

In a separate investigation, Palo Alto Networks identified three malicious apps called PodcastsLounge, PDF-Brain, and PDF-Ninja. All three carried valid Apple Developer ID signatures and had successfully passed notarization.

Apple's notarization process isn't intended to provide a permanent guarantee that an app is safe. It can revoke previously issued approvals and update XProtect to identify malicious software after researchers discover it.

The apps contained malware known as FlutterShell, which used embedded web content to receive instructions from attacker-controlled servers. Attackers could change the malicious instructions remotely without modifying the signed apps.

The approach allowed attackers to update the malware's behavior without submitting the apps for another security review.

PDF-Brain and PDF-Ninja also included working AI document summarization features. Researchers found that documents were routed through attacker-controlled infrastructure before reaching an AI service, creating a way to capture their contents.

Researchers observed browser hijacking and identified additional backdoor capabilities, although parts of the malware were still under development. The findings show how the malware could support more serious attacks, but researchers haven't confirmed widespread document theft.

The company has also strengthened its defenses against commands copied from malicious websites. Starting with macOS Tahoe 26.4, Terminal can display a paste warning when someone who doesn't regularly use the app pastes instructions copied from sources such as browsers or messaging apps.

However, Apple's documentation makes clear that the initial warning depends on how Terminal is being used and where the copied text originated. It isn't a universal check applied to every command.

XProtect can identify and block known malicious commands and AppleScript activity. It works alongside Gatekeeper and Apple's notarization process, adding another layer of protection rather than replacing either one.

The report doesn't suggest that Apple's security protections are ineffective. However, even a fully updated Mac can fall victim to a convincing scam that tricks its owner into running malicious commands.