CVE-2026-84575 Overview
CVE-2026-84575 is an out-of-bounds write vulnerability [CWE-787] affecting multiple Apple operating systems. Processing a maliciously crafted file may lead to unexpected app termination or memory corruption. Apple addressed the flaw with improved bounds checking across its OS family.
The vulnerability requires local access with low privileges and no user interaction. Successful exploitation can compromise confidentiality, integrity, and availability of the affected system. Apple has released coordinated patches spanning iOS, iPadOS, macOS, tvOS, visionOS, and watchOS.
Critical Impact
An attacker with local access can trigger memory corruption by supplying a crafted file to a vulnerable Apple application, potentially leading to arbitrary code execution or denial of service.
Affected Products
- Apple iOS 27 and iPadOS 27 (and earlier)
- Apple macOS Golden Gate 27, macOS Tahoe 26.7, macOS Sequoia 15.8
- Apple tvOS 27, visionOS 27, watchOS 27
Discovery Timeline
- 2026-09-14 - CVE-2026-84575 published to NVD
- 2026-09-16 - Last updated in NVD database
Technical Details for CVE-2026-84575
Vulnerability Analysis
CVE-2026-84575 is classified as an out-of-bounds write (CWE-787). The affected component fails to validate buffer boundaries when parsing a maliciously crafted file. When the parser writes past the allocated buffer, adjacent memory regions become corrupted.
The issue affects file-processing routines shared across Apple's platforms. This shared code path explains the coordinated advisories across iOS, iPadOS, macOS, tvOS, visionOS, and watchOS. Apple's fix introduces additional bounds checking before the write operation executes.
An attacker exploiting this flaw can trigger unexpected application termination. In more severe scenarios, controlled out-of-bounds writes can lead to arbitrary code execution within the process context.
Root Cause
The vulnerability stems from missing or insufficient boundary validation during file parsing. The affected routine calculates a write offset based on attacker-controlled fields inside the file structure. Without proper bounds checking, the write operation extends beyond the allocated buffer, corrupting adjacent memory.
Attack Vector
Exploitation requires local access and the ability to deliver a crafted file to a target application. The attacker needs low-privilege access and no user interaction beyond the initial file processing. See the Apple Support advisories for component-specific details.
No public proof-of-concept exploit code is available for CVE-2026-84575 at this time. Apple has not confirmed exploitation in the wild, and the vulnerability is not listed in the CISA Known Exploited Vulnerabilities catalog.
Detection Methods for CVE-2026-84575
Indicators of Compromise
- Unexpected termination or crash reports from Apple system applications after opening files from untrusted sources
- Crash logs referencing memory access violations (EXC_BAD_ACCESS) or heap corruption in Apple-signed processes
- Presence of unusual file artifacts delivered via email attachments, messaging apps, or removable media
Detection Strategies
- Monitor endpoint telemetry for repeated crashes of Apple applications processing document, media, or archive files
- Correlate file-open events with subsequent process termination or spawning of unexpected child processes
- Review DiagnosticReports and CrashReporter logs on macOS for signatures consistent with out-of-bounds write corruption
Monitoring Recommendations
- Enable centralized collection of macOS unified logs and iOS device management crash reports
- Track OS build versions across the fleet to identify systems missing the patched releases
- Alert on execution of unsigned or newly-introduced binaries following file-parsing crashes
How to Mitigate CVE-2026-84575
Immediate Actions Required
- Update all Apple devices to the patched OS releases: iOS 27, iPadOS 27, macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7, tvOS 27, visionOS 27, and watchOS 27
- Prioritize devices that regularly process files from external or untrusted sources
- Restrict opening of untrusted files until patches are deployed enterprise-wide
Patch Information
Apple released fixes across its platforms as documented in the vendor advisories: Apple Support Article #149034, #149035, #149036, #149037, #149038, #149042, and #149043. The fix introduces improved bounds checking in the affected file-processing routine.
Workarounds
- Avoid opening files from untrusted senders or unknown origins until patches are applied
- Use Mobile Device Management (MDM) to enforce OS update compliance across managed Apple devices
- Isolate high-risk users or systems that cannot immediately update from receiving external file attachments
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.