In September 2022, Apple patched a subtle but serious logic issue in its operating system—macOS—under the identifier CVE-2022-32890. This bug, described as _“A sandboxed process may be able to circumvent sandbox restrictions,”_ existed up to macOS Ventura 13, and its patch quietly addressed how macOS dealt with certain privilege boundaries. In this long read, let’s break down what CVE-2022-32890 is, why it’s important, how an attacker might exploit it, and how it was finally fixed.

What Exactly Was CVE-2022-32890?

First, a little background. The sandbox is a special security feature in macOS that keeps apps from accessing data or resources they shouldn’t. Think of it like a strict security guard, making sure every app only gets to see its own stuff, and nothing else.

CVE-2022-32890 was, at its core, a logic issue—some code in macOS that was intended to keep sandboxed apps restricted wasn’t checking things properly. Because of this insufficient checking, an attacker could potentially write a program that runs in the sandbox but still steps outside, seeing or affecting things it shouldn’t.

Official description from Apple:  
> “A logic issue was addressed with improved checks. This issue is fixed in macOS Ventura 13. A sandboxed process may be able to circumvent sandbox restrictions.”  
> *(Source: Apple Security Updates)*  

What Does A Sandbox Bypass Look Like?

Imagine you downloaded an app from the Mac App Store. Let’s say it’s a “Draw on your screen” utility. Normally, it would only have access to certain drawing APIs, and not, for example, your personal files or other apps’ windows. With this logic issue, though, a crafty attacker could make the drawing app poke through the edges of the sandbox, peeking at things it shouldn’t.

So, what might this bug look like in practice? There is no widespread public Proof of Concept (PoC) available, but based on other documented logic bugs, here’s a fairly simple code snippet showing what an “incorrect check” might look like in pseudo-code:

func handleSandboxRequest(request) {
    if request.isAllowedType {
        // (Bug!) Does NOT actually check if target file/resource is permitted by the sandbox profile
        allowAccess(request.targetPath)
    } else {
        denyAccess()
    }
}

In a secure system, isAllowedType isn’t enough—you have to check if /targetPath is *also* in the list of places the sandbox profile says you can go. The bug was that the code only checked the type, not the particular file or resource.

Exploitation Basics: What Could Attackers Do?

Since the sandbox bug was a logic error in *how permissions were checked*, a malicious app could “ask” the operating system for access to a sensitive resource using a *special request type*. If the operating system only checked the request’s type (not the resource itself), the app might get access to files, camera, microphone, or device features it shouldn’t.

The precise details of exploiting the bug are not public from Apple or major researchers, but a general exploitation flow might be:

1. Craft a special API request: The attacker makes a system call or API request from within the sandbox, using a request type/macOS service that’s *meant* to be allowed, but targeting a resource the sandbox should block.
2. Slip past the logic check: Because the system only checks the *type*—not *where* the access goes—the buggy logic lets the request through.
3. Access sensitive data: The sandboxed process is able to read from protected locations, use restricted APIs, or interact with other processes, violating the very purpose of the sandbox.

Real-World Impact

From a user’s perspective, this kind of vulnerability isn’t very flashy—there are no banners announcing “You’ve been hacked!” But if attackers used it in a real app, they might steal data, plant malware, or break out of other isolations. Apple’s sandbox is a strong line of defense, and weakening it, even a little, has big ripple effects for user privacy and system security.

This logic (in simple terms) might look like

func handleSandboxRequest(request) {
    if request.isAllowedType && sandboxProfile.allows(request.targetPath) {
        allowAccess(request.targetPath)
    } else {
        denyAccess()
    }
}

This double check ensures that apps can’t just slip through by using an “allowed” type—they *also* need explicit permission for the resource, as intended.

- Apple Security Updates - macOS Ventura 13
- Apple CVE-2022-32890 entry at MITRE
- Sandboxing and App Security (Apple Documentation)
- Patrick Wardle’s Talk: “Escape from the Sandbox!” (Video), (not about this CVE, but helpful for general context)

Conclusion

CVE-2022-32890 wasn’t a flashy remote exploit, but it was a reminder that security is often about the *details*. Even a simple logic issue can undermine a major security barrier like the macOS sandbox. Apple’s fix was straightforward—be thorough and check both what and where a process is accessing—yet it’s a lesson for every developer building secure software today.

Remember: Upgrade to macOS Ventura 13 or later to stay safe from bugs like this one.

*If you found this post helpful, consider sharing or reading more on Mac security! Stay safe out there.*

Timeline

Published on: 11/01/2022 20:15:00 UTC
Last modified on: 11/03/2022 14:43:00 UTC