UNIX symbolic link following in iPadOS and Apple iOS - CVE-2021-30855

 

UNIX symbolic link following in iPadOS and Apple iOS - CVE-2021-30855

Published: September 20, 2021


Vulnerability identifier: #VU56726
CSH Severity: Low
CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-30855
CWE-ID: CWE-61
Exploitation vector: Local access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a local application to gain access to otherwise restricted functionality.

The vulnerability exists due to a symlink following issue in Preferences. A local application can create a specially crafted symbolic link to a critical file on the system and  access restricted files.


Affected software

iPadOS
Apple iOS
watchOS
macOS

How to mitigate CVE-2021-30855

Install updates from vendor's website.

iPadOS - update to 15.0 19A346
Apple iOS - update to 15.0 19A346
watchOS - update to 8.0 19R346
macOS - addressed in versions 10.15.7 19H1417, 11.6 20G165

External References

Related Security Bulletins