Apple iOS/macOS 26.6: OOB Write Fixed Remote Attacker Termination Risk
CVE-2026-43803 Published on July 27, 2026

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. A remote attacker may be able to cause unexpected system termination.

NVD

Vulnerability Analysis

CVE-2026-43803 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to be critical as this vulnerability has a high impact to the confidentiality, integrity and availability of this component.

Attack Vector:

NETWORK

Attack Complexity:

LOW

Privileges Required:

NONE

User Interaction:

NONE

Scope:

UNCHANGED

Confidentiality Impact:

HIGH

Integrity Impact:

HIGH

Availability Impact:

HIGH

Weakness Type

What is a Memory Corruption Vulnerability?

The software writes data past the end, or before the beginning, of the intended buffer. Typically, this can result in corruption of data, a crash, or code execution. The software may modify an index or perform pointer arithmetic that references a memory location that is outside of the boundaries of the buffer. A subsequent write operation then produces undefined or unexpected results.

CVE-2026-43803 has been classified to as a Memory Corruption vulnerability or weakness.