Apple’s recent announcement of Memory Integrity Enforcement is full of phrases like “foundational reengineering” and “a new era of memory integrity.” Let's try to cut through the classic Apple tone - confident, polished, a little too self-congratulatory - and try to break down what it actually is and how it actually fits into the big picture.
Don't get me wrong: the technical advancement is real (MIE does make exploit chains harder), but it doesn’t change the fact that actually, API abuse doesn’t care how secure your kernel is. Attackers don’t need to jailbreak a device when they can simply reverse-engineer your app, emulate API calls, and replay stolen tokens — all without tripping any kernel-level alarms. That’s why you still need per-request app attestation.
Secure memory is extremely important, but secure API traffic is critical. So let’s cut through the marketing gloss and focus on what MIE really does—and doesn’t—solve in the broader context of mobile API security.
Memory Integrity Enforcement from Apple
Apple officially announced Memory Integrity Enforcement (MIE) in September 2025, a new kernel-level protection aimed at stopping attackers from modifying memory pages that store executable code.
Apple had quietly deployed this functionality earlier with the release of iOS 17 and macOS Sonoma (macOS 14). Importantly, MIE is hardware-dependent and only supported on devices with Apple’s newer chipsets. According to third-party security analyses, full MIE support is currently available on iPhone 15 Pro and Pro Max, and iPads equipped with the Apple M1 chip and later. Running silently in the background, MIE plays a critical role in making code exploitation and privilege escalation far more difficult.
How does MIE Fit into the Bigger Picture of Apple App Security?
We have previously reviewed Apple’s App Attest and DeviceCheck, which offer helpful primitives for verifying app authenticity. Put simply, MIE protects the device kernel, App Attest is intended to validate the app, and DeviceCheck is intended to track the device reputation. They each operate at different layers of the stack.
However, as we explored in our deep dive on their limitations, App Attest and Device Check are vulnerable to replay attacks, lack full runtime environment visibility, and require complex backend validation logic, which of course is different from what is needed for Google/Android native security, (but that's a whole other discussion - about the need for cross-platform mobile security).
What MIE Actually Does
Apple’s Memory Integrity Enforcement hardens iOS against code injection attacks by ensuring that executable memory regions can’t be tampered with. This disrupts traditional jailbreak techniques, making it harder for malware or tools like Frida to modify app behavior at runtime.
MIE hardens iOS, iPadOS. Specifically, it enforces a strict separation between writable and executable memory, preventing malicious code from being injected and executed in memory regions that are dynamically altered at runtime. MIE extends Apple’s long-standing “Write XOR Execute” (W^X) policy deeper into the kernel memory allocator itself, ensuring that executable pages cannot be retroactively made writable and vice versa. This effectively blocks a broad class of exploits, including JIT spraying and code injection techniques often used in jailbreaks and remote code execution attacks.
What MIE Doesn’t Do
MIE protects device memory. However, it does not protect your APIs from attack:
- MIE does not stop API abuse from bots, scripts, or repackaged apps.
- MIE doesn’t validate that a request came from a genuine, untampered app.
- MIE does nothing to prevent man-in-the-middle (MitM) attacks or stolen secrets being replayed.
Why You Still Need App Attestation—On Every Request
Mobile threat actors are constantly innovating, not just with device exploits, but with API abuse. They reverse-engineer apps, extract secrets, emulate app behavior, and automate attacks from clean devices— and no jailbreak is needed.
That’s why a modern mobile security posture must go beyond the device and shift trust validation to every single API request. Approov’s patented runtime attestation model offers:
- Request-by-Request Proof of App Integrity :
- Every API call from a mobile app must include a short-lived, cryptographically signed Approov token that proves:
- The app is official (not a clone or repackage).
- The runtime environment is uncompromised (no root, debugger, emulator, or instrumentation tools).
- The app’s session hasn’t been hijacked or spoofed.
- Zero Trust for the Device and Network
- Approov treats every request as untrusted until proven otherwise—regardless of whether MIE or other OS-level protections are present. This aligns with modern zero trust principles.
- Resilience Against Device-Level Bypass
- Even on jailbroken devices where MIE is defeated, Approov can detect the compromise and deny valid tokens, preventing API misuse .
The Real-World Attack Surface: Your APIs
So, in conclusion, the core issue remains: most attacks don’t stop at the app—they target your backend APIs.
Without strong request-level validation, attackers can:
- Script credential stuffing attacks
- Automate fake transactions
- Abuse business logic flaws (e.g., Broken Object Level Authorization)
- Replay stolen tokens from valid devices
Approov Complements, Does Not Compete with, OS Security
Apple’s MIE, Apple App Attest, Google Play Integrity, and even HarmonyOS Safety Detect all bring important mobile security elements and are welcome additions, however they are incomplete. For example, Apple’s App Attest fails to protect against jailbroken devices , and Google’s Play Integrity “basic” and “device” levels can be bypassed.
Approov enhances these platform tools with a cross-platform, request-level, zero trust attestation model that:
- Works on iOS, Android, and HarmonyOS
- Detects jailbroken/rooted environments even when OS tools miss them
- Protects both first- and third-party APIs
- Dynamically manages secrets and pins in real-time
As we explored in our detailed breakdown of App Attest and DeviceCheck limitations, these tools help—but don’t fully protect your backend.
Conclusion: Don’t Let (an Important) Kernel Feature Lull You into Complacency
MIE is a meaningful improvement—but it doesn’t close the security loop. Mobile API security requires proof of trust for every request, not just reliance on OS-level protections.
At Approov, we applaud Apple for raising the security baseline. However, relying solely on device-level protections like MIE ignores a glaring reality: mobile threats aren’t just about the device—they’re about abuse of your APIs. This is where Approov delivers the crucial missing layer through per-request dynamic mobile app attestation.
As we explored in our detailed breakdown of App Attest and DeviceCheck limitations, these tools help—but don’t fully protect your backend.
Approov fills this critical gap — and is the missing layer Apple doesn’t provide.
Start your free 30-day Approov trial and see what true mobile API protection looks like.
