Bitdefender’s latest Mac threat report shows adware gaining traction 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 previous report to 34.4%.
Trojans remain the largest category at 45.2%, down from 51.8%. Potentially unwanted apps also dropped from 25.3% to 20.4%.
This change reflects the growing importance of malicious ads, browser redirects, and deceptive software installers that trick users into compromising their Macs.
Web and document threats represented approximately 45% of the larger detection dataset. Including these findings, the share of Trojans rises to 24.8%, that of adware to 18.9% and that of potentially unwanted apps to 11.2%.
The figures reflect threats detected by Bitdefender security products, not confirmed infections in the Mac population. They show how the composition of detected threats has changed, but do not establish whether more Macs are compromised.
Mac malware increasingly relies on user belief
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 executed by the user, it can bypass some of the security checks that macOS normally applies to downloaded apps.
The technique has also become more difficult for security researchers to investigate. In August 2026, Microsoft documented a ClickFix campaign involving more than 250 domains distributing 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 may receive harmless-looking pages instead of malicious instructions, making the campaign harder to detect.
ClickFix campaigns can spread information thieves, who remain a serious threat despite accounting for a relatively small share of detections. Bitdefender found that stealer-class detections increased from about 0.9% to 1.5% of monthly Mac reports between mid-2025 and mid-2026.
Information thieves can target saved browser credentials, session cookies, cryptocurrency wallets, and macOS keychain data. However, Bitdefender could not reliably separate ClickFix activity from other detections, so the report does not establish how much of the theft activity came from that technique.
Apple’s macOS security protections have limitations
The report also highlights malware that has passed Apple’s authentication process, which checks apps for threats before they are 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 authentication.
Apple’s authentication process is not 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 servers controlled by the attackers. Attackers could modify malicious instructions remotely without modifying signed apps.
The approach allowed attackers to update the malware’s behavior without subjecting the apps to another security check.
PDF-Brain and PDF-Ninja also included working AI document summary capabilities. The researchers found that documents were routed through attacker-controlled infrastructure before reaching an AI service, creating a way to capture their contents.
The researchers observed the browser hijacking and identified additional backdoor functionality, although parts of the malware were still in development. The findings show how the malware could support more serious attacks, but researchers have not confirmed widespread document theft.
The company 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 like browsers or messaging apps.
However, Apple’s documentation makes it clear that the initial warning depends on how Terminal is used and where the copied text originated. It is not a universal control applied to every command.
XProtect can identify and block known malicious commands and AppleScript activity. It works in conjunction with Gatekeeper and Apple’s authentication process, adding another layer of protection rather than replacing one.
The report does not suggest that Apple’s security protections are ineffective. However, even a fully updated Mac can fall victim to a convincing scam that tricks the owner into executing malicious commands.
