CyberSecBulletin
CVE-2021-30869Exploited in the wildNVD status: Analyzed

Apple iOS, iPadOS, and macOS Type Confusion

Published Updated By the CyberSecBulletin desk

CVE-2021-30869 is a high-severity access of resource using incompatible type vulnerability in iOS and iPadOS 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 unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 14.4 as the first without the flaw, so updating iOS and iPadOS to that release or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on November 3, 2021, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update iOS and iPadOS to 14.4 or a later version.
  2. Update macOS to 11.2 or 12.5 or 2021, whichever matches your release line, or a later version.
  3. Update iPadOS to 14.4 or a later version.
  4. CISA's required action: Apply updates per vendor instructions.
  5. Read the advisory on support.apple.com for workarounds and exact fixed builds.
  6. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
AppleiOS and iPadOSbefore 14.414.4
ApplemacOSbefore 11.2; before 12.5; before 202111.2, 12.5, 2021
AppleiPadOSbefore 14.414.4
AppleIphone OS12.0 up to, but not including, 12.5.5; 14.0 up to, but not including, 14.412.5.5, 14.4
AppleMac OS X10.14 through 10.14.6; 10.15 through 10.15.6; 10.14.6; 10.15.7Not stated

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
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
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:N/UI:R/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)
CVSS 2.09.3HighNVD

Official description

A type confusion issue was addressed with improved state handling. This issue is fixed in iOS 12.5.5, iOS 14.4 and iPadOS 14.4, macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, Security Update 2021-006 Catalina. A malicious application may be able to execute arbitrary code with kernel privileges. Apple is aware of reports that an exploit for this issue exists in the wild.

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

The underlying weakness: Access of Resource Using Incompatible Type

The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type.

More Access of Resource Using Incompatible Type vulnerabilities (CWE-843)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in iOS and iPadOS

All iOS and iPadOS vulnerabilities

Recent Access of Resource Using Incompatible Type vulnerabilities

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