iPhone 17 raises the barrier against zero-day: Apple’s new “always-on” defense targets crypto wallets and Passkey

With iPhone 17, a continuously active hardware-software defense debuts.

It aims to break the chain of exploits based on memory corruption – the fuel for numerous attacks against crypto wallets and Passkey – thanks to Memory Integrity Enforcement (MIE) technology, a mechanism that controls memory access to reduce the attack surface without requiring user intervention (Apple Security Research).

Essentially, the protection operates in the background and is designed to intercept abuses before they become code execution. Organizations and security projects like OWASP Mobile Top Ten have emphasized for years the importance of memory safety-oriented countermeasures on mobile devices.

According to data collected by teams of analysts who conducted tests on pre-release builds (September 2025), MIE has repeatedly blocked classic exploitation attempts based on memory tagging in laboratory scenarios.

Industry analysts consulted also note that the introduction of MIE increases the technical complexity required to convert a memory bug into a working exploit, shifting attackers’ resources towards less effective vectors.

MIE, in brief: what it is and why now

MIE is a protection for memory integrity that introduces a systematic control over process access to pointers and memory regions.

The goal is to contain classes of bugs, such as buffer overflow and use-after-free, which are often the basis of zero-day attacks aimed at stealing or manipulating signing operations. In this context, the approach is built to reduce the typical maneuvering spaces of exploit chains.

Various public analyses, such as those from Google Project Zero and the Microsoft Security Response Center, highlight that between 60% and 70% of vulnerabilities exploited “in the wild” involve memory safety issues (data updated to 2025).

It should be noted that, precisely for this reason, Apple positions MIE as an always-active defensive layer to protect both the kernel and user processes.

For official details: Memory Integrity Enforcement – Apple Security Research.

How it works, concretely

• Assign tags to memory regions and associate pointers with the corresponding tags, creating a verifiable link between the two.
• Verify each access: if the pointer does not match the memory tag, the operation is blocked immediately.
• Records the event and prevents the continuation of the exploit, reducing the effectiveness of attack chains.

Practical example: use-after-free during a signature

In a typical scenario, a signature library releases an object and malicious code attempts to reuse the related pointer to execute arbitrary code.

With MIE, improper reuse of the pointer generates a tag misalignment: access is denied, causing the exploit to lose stability and preventing manipulation of the signing process. That said, the legitimate operation continues, while the abuse attempt is halted.

Crypto Wallet and Passkey: What Changes for the User

Many attacks targeting wallets and Passkey aim to intercept or alter sensitive data during the signing operation. MIE reduces these attack windows, making it more complex to escalate from a bug to key compromise.

According to statements reported by the industry press, the security company Hacken estimates that MIE “significantly reduces” the likelihood of memory corruption-based attacks for signing purposes (Cointelegraph). Indeed, raising the technical threshold directly impacts the critical transition between vulnerability and key abuse.

What really blocks

• Block/limit: exploits based on memory corruption (buffer overflow, use-after-free) and privilege escalation resulting from invalid memory accesses.
• Does not cover: phishing attacks, social engineering, malicious extensions or web pages that deceive the user.
• Does not replace: the physical protection and isolation of hardware wallets or prudent key management practices.

Zero-day and mercenary spyware: how the risk changes

The exploits used by spyware and mercenary groups typically rely on chains of vulnerabilities. MIE intervenes at the first level, making it more difficult to turn a memory bug into reliable code execution.

As a result, the cost for attackers increases and the effectiveness of attacks decreases, although other vectors remain possible (such as user deception, supply chain attacks, or through components not covered by protection). Yet, the message is clear: the barrier is raised precisely where exploits are most recurrent.

Performance, compatibility, and limitations

Apple describes MIE as an integrated protection at the architecture and system level, designed to operate without manual configurations.

The company assures that the impact on performance in daily activities is minimal, although an independent performance evaluation on iPhone 17 is currently underway (September 2025).

It is important to remember that MIE does not address logical bugs, cryptographic errors, or behaviors induced by social engineering. In other words, it is a piece of defense, not a total solution.

Recommendations for those using wallets on iPhone

• Keep iOS and firmware updated with the official versions as soon as they are released.
• Prefer wallets with independent auditing and documented security controls.
• For significant amounts, consider using the Ledger hardware wallet in combination with the mobile app.
• Reduce the attack surface: disable unnecessary services and treat unexpected links or messages as potential phishing attempts.

FAQ

Do you still need a hardware wallet?

Yes. MIE reduces the risks associated with memory corruption, but it does not replace the physical isolation of keys and the resilience offered by dedicated devices. In this perspective, the combination remains advisable.

Does MIE also protect third-party apps?

Yes, since it operates at the system level, protecting the kernel and user processes. However, the quality of the app’s implementation remains crucial, particularly regarding key management, sandboxing, and the use of updated dependencies.

Outlook

MIE is not a “magic wand,” but it significantly raises the bar: it makes the most common exploits less feasible and forces advanced actors to seek alternative solutions.

If similar defenses are widely adopted in the future, wallet developers might reallocate resources from reactive patches to more security-oriented design and proactive checks. That said, constant risk assessment remains a necessity.