CVE-2024-40821: Apple macOS · Third party app extensions may not receive the correct sandbox restrictions
Affects Apple macOSSource CVE Database V5
Not known to be exploited · CVSS 8.4 High · fixed in 12.7.6 : patch Apple macOS soon.
Data as of 26 Oct 2026, 08:30 UTC
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 13% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 12.7.6
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 29 Jul 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Apple macOS | Affected
| Fixed in– |
AI-suggested
To mitigate CVE-2024-40821, organizations should immediately apply the security updates released by Apple: macOS Monterey 12.7.6, macOS Sonoma 14.6, and macOS Ventura 13.6.8. Beyond patching, organizations should audit installed third party app extensions to identify and remove any that are unnecessary or from untrusted sources. Implement strict application control policies to limit installation of extensions only to vetted software. Employ endpoint detection and response (EDR) solutions capable of monitoring unusual behaviors related to app extensions and sandbox violations. Regularly review macOS security configurations and sandbox policies to ensure compliance with best practices. Educate users and administrators about the risks of installing unverified extensions. For environments with sensitive data, consider restricting local access to macOS devices and enforcing strong authentication and access controls to reduce the risk of local exploitation. Monitoring system logs for sandbox-related anomalies can provide early detection of exploitation attempts.
Description
An access issue was addressed with additional sandbox restrictions. This issue is fixed in macOS Monterey 12.7.6, macOS Sonoma 14.6, macOS Ventura 13.6.8. Third party app extensions may not receive the correct sandbox restrictions.
References
- support.apple.com/en-us/120910 (opens in a new tab)
- support.apple.com/en-us/120911 (opens in a new tab)
- support.apple.com/en-us/120912 (opens in a new tab)
- support.apple.com/en-us/HT214120 (opens in a new tab)
- support.apple.com/en-us/HT214119 (opens in a new tab)
- support.apple.com/en-us/HT214118 (opens in a new tab)
- seclists.org/fulldisclosure/2024/Jul/20 (opens in a new tab)
- seclists.org/fulldisclosure/2024/Jul/18 (opens in a new tab)
- seclists.org/fulldisclosure/2024/Jul/19 (opens in a new tab)
- support.apple.com/kb/HT214120 (opens in a new tab)
- support.apple.com/kb/HT214119 (opens in a new tab)
- support.apple.com/kb/HT214118 (opens in a new tab)