In plain words
Think of a house with a strong lock on the front door, but a weaker lock on a side door that can be opened from the inside. This vulnerability is like finding a way to open the strong lock by going through the weaker side door. In this case, the weaker side door is a security mechanism called sandboxing¹, which is meant to protect the system.
What's broken
The bug is in how macOS handles sandboxing and a security feature called System Integrity Protection (SIP)². An attacker can use this bug to load untrusted code into a process that is supposed to be protected by SIP. This means an attacker could potentially run malicious code on a macOS system, even though SIP is meant to prevent that.
How it actually works
Here's how it works: sandboxing is meant to limit what an application can do on the system. But in this case, an attacker can use sandboxing to their advantage, by tricking the system into loading an untrusted library into a process that has SIP privileges³. This is possible because of a flaw in how macOS handles the interaction between sandboxing and SIP. The attacker can use this flaw to bypass SIP and run malicious code.
Proof of concept
There is a proof of concept (PoC)⁴ that demonstrates this vulnerability. A PoC is like a test that shows the vulnerability is real and can be exploited. In this case, the PoC shows that an attacker can use the bug to load untrusted code into a SIP-entitled process. This makes the vulnerability more urgent, because it shows that the flaw is not just theoretical, but can actually be used by an attacker.
Is it real
It is not clear from the source if this vulnerability is being actively exploited in the wild. However, the fact that there is a PoC makes it more likely that an attacker could use this bug.
What to do
To fix this bug, Apple would need to release a patch or update that fixes the flaw in how macOS handles sandboxing and SIP. Users can also take steps to protect themselves, such as being cautious when opening files or clicking on links from unknown sources.
Terms
- ¹ sandboxing
- , A security mechanism that limits what an application can do on a system
- ² SIP
- , A security feature that protects certain system files and processes from being modified
- ³ SIP privileges
- , A set of privileges that allows a process to perform certain actions on the system
- ⁴ PoC
- , A test or demonstration that shows a vulnerability is real and can be exploited