CyberSecBulletin
CVE-2023-27958NVD status: Modified

macOS: Allocation of Resources Without Limits or Throttling

CVE-2023-27958 is a critical-severity allocation of resources without limits or throttling vulnerability in macOS from Apple, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 13.3, 12.6, 11.7 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 1.62% chance of exploitation within 30 days, higher than 76% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update macOS to 13.3 or 12.6 or 11.7, whichever matches your release line, or a later version.
  2. Read the advisory on support.apple.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ApplemacOSbefore 13.3; before 12.6; before 11.713.3, 12.6, 11.7

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
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.19.1CriticalNVD
CVSS 3.19.1CriticalCISA (ADP)

Official description

The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.3, macOS Monterey 12.6.4, macOS Big Sur 11.7.5. A remote user may be able to cause unexpected system termination or corrupt kernel memory.

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

The underlying weakness: Allocation of Resources Without Limits or Throttling

The product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.

How developers prevent this class of flaw

  • Clearly specify the minimum and maximum expectations for capabilities, and dictate which behaviors are acceptable when resource allocation reaches limits.
  • Limit the amount of resources that are accessible to unprivileged users. Set per-user limits for resources. Allow the system administrator to define these limits. Be careful to avoid CWE-410.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Allocation of Resources Without Limits or Throttling vulnerabilities (CWE-770)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in macOS

All macOS vulnerabilities

Recent Allocation of Resources Without Limits or Throttling vulnerabilities

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