CVE-2026-20698
Published: 25 March 2026
Summary
CVE-2026-20698 is a high-severity Out-of-bounds Write (CWE-787) vulnerability in Apple Ipados. Its CVSS base score is 7.8 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploitation for Privilege Escalation (T1068); ranked at the 2.0th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 SC-39 (Process Isolation) and SI-16 (Memory Protection).
Threat & Defense at a Glance
Threat & Defense Details
Mitigating Controls (NIST 800-53 r5)AI
SI-16 directly implements memory protection mechanisms like bounds checking and isolation to prevent out-of-bounds writes and buffer overflows that corrupt kernel memory from user apps.
SI-2 ensures timely flaw remediation through patching, directly addressing the memory handling vulnerability fixed in Apple OS updates 26.4.
SC-39 enforces process isolation to separate user-space apps from kernel memory, mitigating corruption attempts by low-privilege malicious apps.
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Local kernel memory corruption (out-of-bounds write) directly enables T1068 Exploitation for Privilege Escalation from a malicious app; secondary DoS impact is possible but not a distinct ATT&CK technique match.
NVD Description
The issue was addressed with improved memory handling. This issue is fixed in iOS 26.4 and iPadOS 26.4, macOS Tahoe 26.4, tvOS 26.4, visionOS 26.4, watchOS 26.4. An app may be able to cause unexpected system termination or corrupt kernel…
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memory.
Deeper analysisAI
CVE-2026-20698 is a memory handling vulnerability associated with CWE-787 (Out-of-bounds Write) and CWE-119 (Buffer Overflow), affecting Apple's iOS and iPadOS prior to version 26.4, macOS Tahoe prior to 26.4, tvOS prior to 26.4, visionOS prior to 26.4, and watchOS prior to 26.4. The issue enables an app to cause unexpected system termination or corrupt kernel memory, as rated at CVSS 7.8 (CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).
A local attacker with low privileges, such as one running a malicious app on the device, can exploit this vulnerability with low complexity and no user interaction required. Successful exploitation could result in high-impact denial of service through system crashes or kernel memory corruption, potentially serving as a foundation for privilege escalation or other kernel-level attacks.
Apple's advisories indicate the vulnerability was addressed via improved memory handling in the specified 26.4 updates across affected platforms. Mitigation requires applying these patches promptly, with further details available in security content updates such as https://support.apple.com/en-us/126792, https://support.apple.com/en-us/126794, https://support.apple.com/en-us/126797, https://support.apple.com/en-us/126798, and https://support.apple.com/en-us/126799.
Details
- CWE(s)