CVE-2022-42856 is a type confusion vulnerability in Apple iOS. CISA added it to the Known Exploited Vulnerabilities catalogue on 14 December 2022, which means attackers have used it in real attacks. Apple iOS contains a type confusion vulnerability when processing maliciously crafted web content leading to code execution.
What a type confusion vulnerability means in iOS
A type confusion bug means the operating system or browser engine treats one kind of object as if it were another. In practice, that can corrupt memory, break security assumptions, and turn ordinary content processing into an execution path for an attacker.
On iOS, this matters because the vulnerable code path is reachable while handling web content, so the trigger can come from a remote page rather than a local app install. When the flaw is in content parsing or rendering, the attacker only needs the victim to load the malicious content.
Why maliciously crafted web content is dangerous
Web content is one of the highest-risk input surfaces on a mobile platform because it is complex, externally supplied, and heavily exercised. A flaw in that pipeline can become a reliable remote code execution opportunity if the attacker can shape data so the engine misinterprets it.
This is why the issue is more serious than a simple crash. Once type confusion is reached, the bug can undermine memory safety and provide a stepping stone toward code execution, sandbox escape attempts, or follow-on exploitation depending on the surrounding defenses.
Exposure, scope, and how organisations assess it
For this CVE, exposure should be assessed from the outside in: inventory the iOS devices and apps in use, identify which devices can reach untrusted web content, and compare that estate against the vendor advisory and the NIST National Vulnerability Database entry and the CVE Program record.
Because CISA placed this vulnerability in the KEV catalogue, organisations should treat internet-facing exposure and unmanaged devices as priority cases. If mobile fleets are partially managed, the practical question is not only whether the patch exists, but whether every affected device can be identified and updated in time.
Remediation and detection after exploitation
The primary remediation is to apply the vendor fix as soon as it is available to your fleet, then verify that high-risk devices have actually received it. Where patching is delayed, reduce exposure by limiting untrusted browsing, tightening web content handling where policy allows, and using mobile management controls to keep vulnerable devices off sensitive networks and accounts.
Detection should focus on signs of compromise rather than the vulnerability alone. Review for unusual crashes in browser or WebKit-related processes, unexpected app launches, abnormal network activity after web browsing, and any post-exploitation indicators that suggest the device was used to stage further access. The Vulnerability Management Guide is useful for organising this kind of prioritisation and verification workflow, while the MITRE ATT&CK Enterprise Matrix helps map likely post-compromise behaviour such as execution, persistence, and lateral movement.
Risk and Threat Considerations
This vulnerability is dangerous because it combines a common user action, loading web content, with a memory-safety failure that can become remote code execution. Once an attacker can trigger the bug through content delivery, the device may be compromised before the user sees any obvious warning.
Failure mechanism: Type confusion lets attacker-controlled data be interpreted as the wrong object type, which can corrupt memory and redirect execution.
Impact: Successful exploitation can lead to arbitrary code execution on the device, followed by theft of data, session abuse, or further compromise if the device trusts sensitive accounts and services.
Standards & Framework Alignment
This section maps relevant standards and security frameworks to the operational risks and controls described in this guidance.
MITRE ATT&CK addresses the attack surface, NIST SP 800-53 Rev 5 sets the technical controls, and ISO/IEC 27001:2022 defines the regulatory obligations.
| Framework | Control / Reference | Relevance |
|---|---|---|
| MITRE ATT&CK | T1203 — Exploitation for Client Execution | Malicious web content drives code execution on the client device. |
| Recommendation — Monitor client-side exploit chains and hunt for execution after suspicious web content is rendered. | ||
| NIST SP 800-53 Rev 5 | SI-3 — Malicious Code Protection | Maliciously crafted web content can deliver exploit payloads through trusted content paths. |
| RA-5 — Vulnerability Monitoring and Scanning | Exposure must be identified against vulnerable iOS assets and internet-reachable content paths. | |
| IR-4 — Incident Handling | Post-exploitation review is needed when a client-side exploit may have succeeded. | |
| Recommendation — Strengthen malicious code controls for web-facing endpoints and mobile-managed devices. Track affected devices and verify remediation status against active vulnerability intelligence. Investigate suspicious mobile device behaviour as a potential compromise event. | ||
| ISO/IEC 27001:2022 | A.8.8 — Management of technical vulnerabilities | The CVE requires patch prioritisation, exposure review, and remediation verification. |
| Recommendation — Prioritise remediation and validate closure for vulnerable iOS devices. | ||
Related resources from NHI Mgmt Group
Deepen Your Knowledge
Free weekly newsletter
Subscribe to the NHI & AI Identity Journal
The latest on NHI and Agentic AI security – articles, research, breaches, news and events every week.
Bonus 33% off our NHI Course when you subscribe.
Reviewed and updated by the NHIMG editorial team on October 17, 2026.
NHI Mgmt Group — the #1 independent authority on Non-Human Identity, IAM, and Agentic AI security. nhimg.org