Description

An integer overflow was addressed with improved input validation. This issue is fixed in iOS 26.6.1 and iPadOS 26.6.1, macOS Tahoe 26.6.2. Processing an image may lead to arbitrary code execution.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "8.8",
  "pubDate": "2026-08-17T22:17:25.293Z",
  "pubdate": "2026-08-17T22:17:25.293Z",
  "executiveSummary": "An integer overflow vulnerability has been identified within the image processing pipeline affecting iOS 26.6.1, iPadOS 26.6.1, and macOS Tahoe 26.6.2. This flaw arises from insufficient input validation when parsing untrusted image structures, leading to arithmetic overflows during memory allocation calculations. Successful exploitation of this vulnerability permits an adversary to achieve arbitrary code execution within the context of the affected application or system process. The risk implications are severe, as an attacker can compromise the confidentiality, integrity, and availability of the underlying operating system. Attacker capabilities rely on inducing a target user to process a maliciously crafted image file. Exploitation requirements typically involve delivering the payload via web content, messaging applications, or local file access where automated or manual image rendering occurs. Due to the potential for complete system compromise or application takeover via memory corruption, immediate remediation is strongly advised through the application of the officially provided software updates.",
  "technicalDetails": "The vulnerability is an integer overflow flaw localized within the image processing subsystem of the affected operating systems. The root cause stems from inadequate input validation and bounds checking prior to performing arithmetic operations on size and dimension parameters derived from incoming image files. When the image parser evaluates maliciously crafted header data containing oversized values, the arithmetic calculation wraps around, resulting in an integer overflow. This typically yields an allocation size significantly smaller than the actual buffer required to store the decoded image payload.\nDuring the exploitation phase, the undersized memory buffer is allocated on the heap while the downstream image decoding routine writes data based on the original, unconstrained dimensions. This discrepancy triggers a classic heap-based buffer overflow condition, enabling the overwriting of adjacent memory structures, function pointers, or critical control data. The attack flow commences when a victim processes a specially crafted image file through an affected component on iOS 26.6.1, iPadOS 26.6.1, or macOS Tahoe 26.6.2. No authentication or elevated privileges are required to initiate the attack sequence, provided the victim application automatically parses or renders the malicious image data. Network exposure depends on the vector of delivery, such as viewing a compromised web page, opening an email attachment, or receiving the file via messaging protocols.\nThe payload behavior involves manipulating the corrupted heap metadata to redirect execution flow. By precisely crafting the heap layout, an attacker can achieve arbitrary code execution with the privileges of the process handling the image decode operation. Post-exploitation impact ranges from local privilege escalation to persistent installation of malware, depending on sandbox restrictions and the specific privileges of the target host process."
}