CVE Vulnerabilities

CVE-2019-8789

Improper Link Resolution Before File Access ('Link Following')

Published: Dec 18, 2019 | Modified: Dec 23, 2019
CVSS 3.x
5.5
MEDIUM
Source:
NVD
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:P/I:N/A:N
RedHat/V2
RedHat/V3
Ubuntu

A validation issue existed in the handling of symlinks. This issue was addressed with improved validation of symlinks. This issue is fixed in iOS 13.2 and iPadOS 13.2, macOS Catalina 10.15.1. Parsing a maliciously crafted iBooks file may lead to disclosure of user information.

Weakness

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.

Affected Software

Name Vendor Start Version End Version
Ipados Apple * 13.2 (excluding)
Iphone_os Apple * 13.2 (excluding)
Mac_os_x Apple * 10.15.1 (excluding)

Potential Mitigations

  • 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.

References