SB2021102802 - Multiple vulnerabilities in Apple Safari



SB2021102802 - Multiple vulnerabilities in Apple Safari

Published: October 28, 2021

Security Bulletin ID SB2021102802
CSH Severity
High
Patch available
YES
Number of vulnerabilities 4
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 25% Medium 25% Low 50%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 4 vulnerabilities.


1) Security restrictions bypass (CVE-ID: CVE-2021-30887)

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote attacker to bypass implemented security restrictions.

The vulnerability exists due an error within the WebKit component. A remote attacker can trick the victim to open a specially crafted website and bypass Content Security Policy restrictions.


2) Information disclosure (CVE-ID: CVE-2021-30888)

CWE-ID: CWE-200 - Exposure of sensitive information to an unauthorized actor

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear


The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists in WebKit. A malicious website using Content Security Policy reports may be able to leak information via redirect behavior.


3) Buffer overflow (CVE-ID: CVE-2021-30889)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber


The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error when processing HTML content in WebKit. A remote attacker can create a specially crafted website, trick the victim into opening it, trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.


4) Universal Cross-site scripting (CVE-ID: CVE-2021-30890)

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Green


The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The vulnerability exists due to insufficient sanitization of user-supplied data in WebKLit. A remote attacker can trick the victim to follow a specially crafted link and execute arbitrary HTML and script code in user's browser in context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.


Remediation

Install update from vendor's website.