CVE-2025-43240
📋 TL;DR
This CVE describes a logic flaw in macOS and Safari where a download's origin may be incorrectly associated, potentially allowing malicious downloads to appear legitimate. It affects macOS users before Sequoia 15.6 and Safari users before version 18.6. The vulnerability could enable social engineering attacks by misrepresenting download sources.
💻 Affected Systems
- macOS
- Safari
📦 What is this software?
Macos by Apple
macOS is Apple's desktop and laptop operating system powering Mac computers used by millions of professionals, developers, creative professionals, and enterprise users worldwide. Built on a Unix foundation with the Darwin kernel and modern Cocoa frameworks, macOS delivers a seamless ecosystem integr...
Learn more about Macos →Safari by Apple
⚠️ Risk & Real-World Impact
Worst Case
Users download malicious files believing they come from trusted sources, leading to system compromise, data theft, or ransomware infection.
Likely Case
Users are tricked into downloading malware disguised as legitimate software, potentially leading to credential theft or adware installation.
If Mitigated
Users verify downloads through additional means or have endpoint protection that detects malicious files despite the origin misrepresentation.
🎯 Exploit Status
Exploitation requires user interaction (downloading a file) and social engineering to convince users the download is legitimate.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: macOS Sequoia 15.6, Safari 18.6
Vendor Advisory: https://support.apple.com/en-us/124149
Restart Required: Yes
Instructions:
1. Open System Settings on macOS. 2. Go to General > Software Update. 3. Install macOS Sequoia 15.6 update. 4. For Safari, update through App Store or System Settings > General > Software Update.
🔧 Temporary Workarounds
Use alternative browser
macOSTemporarily use Chrome, Firefox, or Edge browsers which are not affected by this Safari-specific vulnerability.
Disable automatic downloads
macOSConfigure Safari to ask before downloading files to add an extra verification step.
Open Safari > Settings > General > Uncheck 'Open safe files after downloading'
🧯 If You Can't Patch
- Educate users to verify download sources through multiple channels before opening files.
- Implement endpoint detection and response (EDR) solutions to detect malicious files regardless of perceived origin.
🔍 How to Verify
Check if Vulnerable:
Check macOS version in System Settings > General > About. Check Safari version in Safari > About Safari.Check Version:
sw_vers (macOS), /usr/bin/safaridriver --version (Safari)Verify Fix Applied:
Confirm macOS version is 15.6 or later and Safari version is 18.6 or later.📡 Detection & Monitoring
Log Indicators:
- Unusual download patterns from unexpected sources in browser logs
- Files with mismatched signatures or hashes from claimed sources
Network Indicators:
- Downloads originating from domains not matching claimed sources in proxy logs
SIEM Query:
source="*browser*" download OR file_save AND (src_ip!=expected_domain OR user_agent="*Safari*" AND version<18.6)