CyberSecBulletin
CVE-2023-42892NVD status: Modified

macOS: Use After Free

CVE-2023-42892 is a high-severity use after free vulnerability in macOS from Apple, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 13.6, 12.7, 14.2 as the first without the flaw, so updating macOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.19% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update macOS to 13.6 or 12.7 or 14.2 or 13.6.3, whichever matches your release line, or a later version.
  2. Read the advisory on support.apple.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
ApplemacOSbefore 13.6; before 12.7; before 14.2; 13.0 up to, but not including, 13.6.3; 14.0 up to, but not including, 14.2; 12.0 up to, but not including, 12.7.213.6, 12.7, 14.2, 13.6.3, 12.7.2

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)

Official description

A use-after-free issue was addressed with improved memory management. This issue is fixed in macOS Ventura 13.6.3, macOS Sonoma 14.2, macOS Monterey 12.7.2. A local attacker may be able to elevate their privileges.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use After Free

The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

How developers prevent this class of flaw

  • Choose a language that provides automatic memory management.
  • When freeing pointers, be sure to set them to NULL once they are freed. However, the utilization of multiple or complex data structures may lower the usefulness of this strategy.

More Use After Free vulnerabilities (CWE-416)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in macOS

All macOS vulnerabilities

Recent Use After Free vulnerabilities

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