# Apple Patches ImageIO Integer Overflow (CVE-2026-65346) Exploitable via Malicious Images

> Apple fixed CVE-2026-65346, an integer-overflow flaw (CWE-190, CVSS 3.1 8.8) in its ImageIO image-decoding framework that can lead to arbitrary code execution when a device processes a maliciously crafted image. Reported by Nik Tsytsarkin of Meta's Red Team X and patched in iOS 26.6.1, iOS/iPadOS 18.7.10, macOS Tahoe 26.6.2, and visionOS 26.6.1, with no confirmed in-the-wild exploitation but a documented history of ImageIO-class bugs being weaponized as zero-click spyware delivery vectors.

- **Published:** 2026-08-18T00:00:00Z
- **Last reviewed:** 2026-08-18T00:00:00Z
- **Canonical:** https://intel.threadlinqs.com/threat/TL-2026-2060
- **ID:** TL-2026-2060
- **Severity:** HIGH (CVSS 8.8)
- **Category:** VULNERABILITY
- **Status:** PATCHED
- **Detections:** 9 · **IOCs:** 13 (full data via the Threadlinqs MCP server — Purple tier)
- **CVEs:** CVE-2026-65346

## Description

CVE-2026-65346 is an integer-overflow vulnerability in ImageIO, the low-level Apple framework that every first-party and third-party app on iOS, iPadOS, macOS, and visionOS uses to decode image formats such as JPEG, PNG, GIF, HEIC, and TIFF. Apple's advisory states the issue "was addressed with improved input validation" and that "processing an image may lead to arbitrary code execution." NVD assigns CWE-190 (Integer Overflow or Wraparound) and a CVSS 3.1 base score of 8.8 (AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) — network-reachable, low attack complexity, no privileges required, but user interaction required (the target must view or otherwise cause the device to process the malicious image). The bug was reported by Nik Tsytsarkin of Meta's internal offensive-security team, Red Team X, and fixed on 2026-08-18 in iOS 26.6.1 and iPadOS 26.6.1 (iPhone 11 and later; supported iPad Pro/Air/iPad/mini models), macOS Tahoe 26.6.2, visionOS 26.6.1, and — for legacy hardware (iPhone XS, XS Max, XR) — iOS 18.7.10 and iPadOS 18.7.10.

Apple's own advisories give no indication the bug has been exploited in the wild, and no public proof-of-concept exists. However, The Register and Forbes both frame the flaw as a standout fix precisely because of ImageIO's exploitation history: Jamf senior enterprise strategy manager Adam Boynton is quoted noting that "image parsing flaws have historically been the delivery mechanism for zero-click spyware targeting executives." The two documented precedents cited are FORCEDENTRY (CVE-2021-30860), a CoreGraphics/PDF integer-overflow chain NSO Group used to deliver Pegasus spyware via iMessage with zero clicks, and Operation Triangulation (MITRE ATT&CK Campaign C0054), a 2023-disclosed iMessage zero-click campaign that abused ImageIO's format-sniffing behavior — ImageIO ignores file extensions and guesses the true format from content, so a maliciously-crafted file disguised as a GIF ('fake gif' trick) can reach any of 20+ obscure image codecs — to deploy the TriangleDB implant (microphone recording, iCloud Keychain extraction, SQLite data theft via targeted searches of app-container files and directories, GPS/network-based location estimation), a purely memory-resident implant with no on-disk persistence. Reaching TriangleDB required chaining the initial ImageIO/font-parsing memory-corruption bug with a separate privilege-escalation step that abused an undocumented hardware MMIO feature — described in Kaspersky's "last (hardware) mystery" research — to defeat the kernel's hardware-based memory protections before the implant could execute with elevated privileges.

CVE-2026-65346 differs from both precedents in one material respect: its CVSS vector requires user interaction (UI:R), unlike the zero-click, no-interaction delivery FORCEDENTRY and Triangulation achieved — though Jamf's Boynton cautioned this distinction is thin in practice, noting attackers exploiting this bug class "don't need you to install anything ... only to receive an image." No threat actor or campaign has been attributed to CVE-2026-65346 itself, and Apple has not flagged it as actively exploited or added it to CISA's Known Exploited Vulnerabilities catalog. (Operation Triangulation's own attribution remains disputed: Russia's FSB publicly claimed the campaign was NSA-conducted, a claim Kaspersky's independent technical research neither confirms nor attributes to any named actor.) The same iOS 26.6.1 update also patches CVE-2026-65329 (a separate Telephony/IPSec authentication-bypass flaw) and roughly twenty WebKit and three kernel issues, and iOS 18.7.10 separately patches a second, distinct ImageIO code-execution bug (CVE-2026-43818) and a kernel-privileged AVEVideoEncoder buffer overflow (CVE-2026-64747) — none of which are in scope for this record.

## MITRE ATT&CK

- T1566.001 Phishing: Spearphishing Attachment
- T1203 Exploitation for Client Execution
- T1204.002 User Execution: Malicious File
- T1036 Masquerading
- T1555.001 Credentials from Password Stores: Keychain
- T1123 Audio Capture
- T1005 Data from Local System
- T1588.006 Obtain Capabilities: Vulnerabilities
- T1404 Exploitation for Privilege Escalation
- T1420 File and Directory Discovery
- T1430 Location Tracking

## Sources

- [Apple plugs image-processing hole ripe for spyware abuse](https://www.theregister.com/security/2026/08/18/apple-plugs-image-processing-hole-ripe-for-spyware-abuse/5289031)
- [iOS 26.6.1 And iOS 18.7.10—Update Now Warning For All iPhone Users](https://www.forbes.com/sites/kateoflahertyuk/2026/08/18/ios-2661-and-ios-18710-update-now-warning-for-all-iphone-users/)
- [About the security content of iOS 26.6.1 and iPadOS 26.6.1](https://support.apple.com/en-us/148282)
- [About the security content of macOS Tahoe 26.6.2](https://support.apple.com/en-us/148281)
- [CVE-2026-65346 Detail](https://cve.threatint.com/CVE/CVE-2026-65346)
- [Home | Meta Red Team X](https://rtx.meta.security/)
- [iOS Zero-Day Attacks: Experts Uncover Deeper Insights into Operation Triangulation](https://thehackernews.com/2023/10/operation-triangulation-experts-uncover.html)
- [New Report Exposes Operation Triangulation's Spyware Implant Targeting iOS Devices](https://thehackernews.com/2023/06/new-report-exposes-operation.html)
- [Operation Triangulation: The last (hardware) mystery](https://securelist.com/operation-triangulation-the-last-hardware-mystery/111669/)
- [Operation Triangulation, Campaign C0054](https://attack.mitre.org/campaigns/C0054/)

## Full data

Detection queries (Splunk SPL / Microsoft KQL / Sigma) and IOC values require the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp

Canonical: https://intel.threadlinqs.com/threat/TL-2026-2060