CVE-2025-43273 Overview
CVE-2025-43273 is a sandbox escape vulnerability affecting Apple macOS. A sandboxed process can circumvent sandbox restrictions due to insufficient permission enforcement [CWE-693: Protection Mechanism Failure]. Apple addressed the issue by adding additional sandbox restrictions in macOS Sequoia 15.6 and macOS Sonoma 14.8.
The vulnerability carries a CVSS score of 9.1 and is reachable over the network without user interaction, according to the published CVSS vector. Successful exploitation breaks the confidentiality and integrity guarantees that the App Sandbox is designed to enforce, exposing user data and system resources outside the intended sandbox boundary.
Critical Impact
A sandboxed application can escape its container and access resources outside its sandbox profile, undermining one of macOS's core defense-in-depth controls.
Affected Products
- Apple macOS Sonoma versions prior to 14.8
- Apple macOS Sequoia versions prior to 15.6
- Applications relying on macOS App Sandbox for isolation
Discovery Timeline
- 2025-07-30 - CVE-2025-43273 published to the National Vulnerability Database
- 2025-07-30 - Apple releases macOS Sequoia 15.6 and macOS Sonoma 14.8 addressing the issue
- 2026-04-02 - Last updated in NVD database
Technical Details for CVE-2025-43273
Vulnerability Analysis
The flaw is classified under [CWE-693], a protection mechanism failure. The macOS App Sandbox restricts what a process can read, write, and execute by mediating access through entitlements and sandbox profiles. When a sandboxed process can reach functionality that the sandbox profile was meant to deny, the isolation guarantee collapses.
Apple's advisory states the issue was addressed with additional sandbox restrictions, indicating the original profile or permission check did not cover all paths that grant access to protected resources. The fix narrows what a sandboxed process is permitted to invoke.
The consequence is that malicious code running inside a sandboxed app, such as a Mac App Store application or a browser content process, can read or modify data that should remain isolated. This breaks the trust boundary the operating system advertises to users and developers.
Root Cause
The root cause is an incomplete sandbox policy. A permission check failed to restrict a code path that allowed a sandboxed process to reach functionality outside its intended privilege envelope. Apple did not publish the specific subsystem or sandbox profile entry that was modified.
Attack Vector
An attacker must execute code inside a sandboxed process on the target macOS host. This is typically achieved by delivering a malicious application or by chaining a memory corruption bug in a sandboxed component such as a browser renderer. Once inside the sandbox, the attacker invokes the vulnerable code path to access resources that the sandbox profile was meant to block. No user interaction beyond running the sandboxed app is required for the escape itself.
The vulnerability is described in prose in Apple's advisory. See the Apple Support Document #125112 and Apple Support Document #124149 for the vendor's technical description.
Detection Methods for CVE-2025-43273
Indicators of Compromise
- Sandboxed processes spawning child processes or opening file handles outside their declared container path under ~/Library/Containers/
- Unexpected XPC service calls or Mach message traffic from App Store applications to system services they do not normally communicate with
- macOS Unified Log entries from sandboxd showing allowed operations that previously generated deny entries on patched hosts
Detection Strategies
- Baseline normal per-application sandbox behavior using endpoint telemetry, then alert on deviations such as access to ~/Library/Mail, ~/Library/Messages, or Keychain paths from unrelated sandboxed apps
- Hunt for processes loading unexpected dynamic libraries or invoking posix_spawn with arguments outside their bundle
- Correlate sandbox boundary crossings with subsequent network egress to detect post-escape data staging
Monitoring Recommendations
- Forward Endpoint Security framework events (ES_EVENT_TYPE_NOTIFY_EXEC, ES_EVENT_TYPE_NOTIFY_OPEN) to a central analytics platform for retroactive hunting
- Track macOS version distribution across the fleet and alert on hosts still running macOS Sonoma below 14.8 or Sequoia below 15.6
- Monitor for installation of unsigned or ad-hoc signed applications, which are common delivery vectors for sandbox-escape payloads
How to Mitigate CVE-2025-43273
Immediate Actions Required
- Update macOS Sonoma hosts to version 14.8 and macOS Sequoia hosts to version 15.6 or later
- Inventory endpoints running unsupported macOS releases and prioritize them for upgrade or replacement
- Restrict installation of applications from unidentified developers using Gatekeeper and MDM policy
Patch Information
Apple released fixes in macOS Sequoia 15.6 and macOS Sonoma 14.8. Refer to the Apple Support Document #125112 and Apple Support Document #124149 for the full advisory and complete list of addressed issues. Additional community discussion is available on the Full Disclosure July 2025 thread and Full Disclosure September 2025 thread.
Workarounds
- No vendor-supplied workaround exists; apply the macOS update as the only supported remediation
- Reduce attack surface by limiting which sandboxed applications users may install through MDM allow-lists
- Enforce System Integrity Protection (SIP) and FileVault to limit the value of any data exposed by a successful sandbox escape
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
