macOS: Improper Link Resolution Before File Access
CVE-2023-42844 is a high-severity improper link resolution before file access vulnerability in macOS from Apple, with a CVSS 3.1 base score of 7.5 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 14.1, 13.6, 12.7 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 1.73% chance of exploitation within 30 days, higher than 78% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update macOS to 14.1 or 13.6 or 12.7, whichever matches your release line, or a later version.
- Read the advisory on support.apple.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Apple | macOS | before 14.1; before 13.6; before 12.7 | 14.1, 13.6, 12.7 |
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
- HighAll data handled by the component can be read.
- Integrity
- NoneNothing can be modified.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.
Official description
This issue was addressed with improved handling of symlinks. This issue is fixed in macOS Sonoma 14.1, macOS Monterey 12.7.1, macOS Ventura 13.6.1. A website may be able to access sensitive user data when resolving symlinks.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Link Resolution Before File Access
The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.
How developers prevent this class of flaw
- Follow the principle of least privilege when assigning access rights to entities in a software system. Denying access to a file can prevent an attacker from replacing that file with a link to a sensitive file. Ensure good compartmentalization in the system to provide protected areas that can be trusted.
More Improper Link Resolution Before File Access vulnerabilities (CWE-59)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Advisories
- support.apple.com/en-us/HT213983Release Notes
- support.apple.com/en-us/HT213984Release Notes
- support.apple.com/en-us/HT213985Release Notes
- support.apple.com/kb/HT213983Release Notes
- support.apple.com/kb/HT213984Release Notes
- support.apple.com/kb/HT213985Release Notes
Third-party and government advisories
- seclists.org/fulldisclosure/2023/Oct/21Mailing List, Third Party Advisory
- seclists.org/fulldisclosure/2023/Oct/24Mailing List, Third Party Advisory
- seclists.org/fulldisclosure/2023/Oct/26Mailing List, Third Party Advisory
Other vulnerabilities in macOS
- 8.8 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
- 7.5 High severity
Recent Improper Link Resolution Before File Access vulnerabilities
- 8.1 High severity
- 7.3 High severity
- 8.4 High severity
- 7.8 High severity
- 8.8 High severity
- 7.8 High severity
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