Zero-day vulnerability in Apple iOS

Use-after-free
CVE-2021-30858

Vulnerability details

Advisory: SB2021091318 - Remote code execution in Apple iOS

Vulnerable component: Apple iOS

CVE-ID: CVE-2021-30858

CVSSv3 score: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:H/RL:O/RC:C

CWE-ID: CWE-416 - Use After Free

Description:

The vulnerability allows a remote attacker to compromise vulnerable system.

The vulnerability exists due to a use-after-free error when processing HTML content in WebKit. A remote attacker can trick the victim to visit a specially crafted web page, trigger a use-after-free error and execute arbitrary code on the system.

Successful exploitation of the vulnerability may allow an attacker to compromise vulnerable system.

Note, the vulnerability is being actively exploited in-the-wild.

External links:

https://support.apple.com/en-us/HT212807

About zero-day vulnerabilities

Zero-day vulnerability is an undisclosed vulnerability in software that hackers can exploit to compromise computer programs, gain unauthorized access to sensitive data, penetrate networks, etc. We consider vulnerability a zero-day when there is no solution provided from software vendor and the vulnerability is being actively exploited by malicious actors.

Zero-day candidate is a potential zero-day vulnerability in software which might have been used in targeted attacks, however there is no evidence to support this suggestion.