CVE-2025-43354 Overview
CVE-2025-43354 is a sensitive information disclosure vulnerability affecting multiple Apple operating systems. The flaw stems from insufficient data redaction in system logs, allowing a locally installed application to read sensitive user data that should have been sanitized before being written to log files. Apple addressed the issue with improved data redaction in iOS 26, iPadOS 26, macOS Tahoe 26, tvOS 26, visionOS 26, and watchOS 26. The vulnerability is classified under CWE-532: Insertion of Sensitive Information into Log File.
Critical Impact
An app installed on an affected Apple device may read sensitive user data from system logs, enabling local information disclosure without elevated privileges.
Affected Products
- Apple iOS and iPadOS (versions prior to 26)
- Apple macOS Tahoe (versions prior to 26) and Apple tvOS (versions prior to 26)
- Apple visionOS and watchOS (versions prior to 26)
Discovery Timeline
- 2025-09-15 - CVE-2025-43354 published to the National Vulnerability Database (NVD)
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-43354
Vulnerability Analysis
The vulnerability is a logging issue in which Apple operating system components wrote sensitive user data into system log entries without applying adequate redaction. Log files on Apple platforms are accessible to processes with standard user privileges, meaning any application that reads unified log streams could observe data that policy expected to be masked.
Exploitation requires local access and some user interaction, such as installing or launching a malicious application. No privileges are required beyond those granted to a normal sandboxed app. The impact is limited to confidentiality; integrity and availability are not affected.
Root Cause
The root cause is improper application of privacy qualifiers in logging APIs. Apple's unified logging system relies on developers marking sensitive fields as private so that the operating system replaces them with <private> placeholders in log output. When a field is logged with public visibility or without the appropriate qualifier, sensitive values are stored verbatim in the log store. This class of defect is tracked as CWE-532.
Attack Vector
An attacker distributes an application through the App Store, TestFlight, enterprise provisioning, or sideloading. After a user runs the app, it queries the local log store using supported diagnostic interfaces such as OSLogStore or command line tooling like log show on macOS. The app then parses returned entries for unredacted personal information, tokens, identifiers, or file paths that reveal user activity. See the Apple Security Update Advisory 125108 and the corresponding Full Disclosure Post #49 for additional context.
Detection Methods for CVE-2025-43354
Indicators of Compromise
- Applications invoking OSLogStore APIs or executing log show, log stream, or sysdiagnose collection commands outside expected diagnostic workflows.
- Unexpected reads of files under /var/db/diagnostics/ or /var/db/uuidtext/ on macOS endpoints.
- Apps requesting the com.apple.private.logging entitlement or bundling embedded log parsing utilities.
Detection Strategies
- Baseline the set of applications that legitimately access unified logs and alert on new or unsigned processes reading the log store.
- Inspect Mobile Device Management (MDM) inventory for installed apps that declare diagnostic or logging capabilities without a clear business justification.
- Correlate log-store access with subsequent network egress to identify staging of exfiltrated data.
Monitoring Recommendations
- Forward endpoint telemetry, including process execution and file access events, into a central analytics platform for retrospective hunting.
- Track OS version compliance and flag devices still running pre-26 releases of iOS, iPadOS, macOS, tvOS, visionOS, or watchOS.
- Review developer and enterprise-signed application distribution channels for apps that read diagnostic data on launch.
How to Mitigate CVE-2025-43354
Immediate Actions Required
- Update all Apple devices to iOS 26, iPadOS 26, macOS Tahoe 26, tvOS 26, visionOS 26, and watchOS 26 as delivered by Apple.
- Audit installed applications on managed fleets and remove apps that access diagnostic logs without justification.
- Rotate any credentials, tokens, or identifiers suspected of appearing in logs collected on unpatched devices.
Patch Information
Apple resolved CVE-2025-43354 by improving data redaction in the affected logging paths. Fixes are documented in Apple Security Advisory 125108, Advisory 125114, Advisory 125115, and Advisory 125116. Administrators should enforce the updated builds through MDM compliance policies.
Workarounds
- Restrict installation of third-party or sideloaded applications on managed devices until updates are applied.
- Disable non-essential diagnostic logging profiles that increase the volume of data written to the unified log store.
- Limit enterprise-signed applications to a curated allowlist reviewed for log-access behavior.
# Example MDM query to identify devices below the fixed build
mdm-cli devices list --filter "osVersion<26" --fields udid,model,osVersion,user
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
