Multiple vulnerabilities in Apple macOS

Published: 2020-11-06

Risk	Critical
Patch available	YES
Number of vulnerabilities	4
CVE-ID	CVE-2020-27930 CVE-2020-27932 CVE-2020-27950 CVE-2020-27904
CWE-ID	CWE-119 CWE-843 CWE-125
Exploitation vector	Network
Public exploit	Vulnerability #1 is being exploited in the wild. Vulnerability #2 is being exploited in the wild. Vulnerability #3 is being exploited in the wild. Public exploit code for vulnerability #4 is available.
Vulnerable software Subscribe	macOS Operating systems & Components / Operating system
Vendor	Apple Inc.

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) Memory corruption

EUVDB-ID: #VU48171

Risk: Critical

CVSSv3.1: 8.4 [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]

CVE-ID: CVE-2020-27930

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

Description

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

The vulnerability exists due to a boundary error when processing fonts within the FontParser component. A remote attacker can create a specially crafted document or web page, 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.

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

Mitigation

Install updates from vendor's website.

Vulnerable software versions

macOS: 10.15 19A583 - 10.15.7 19H2

External links

http://support.apple.com/en-us/HT211947

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.

2) Type Confusion

EUVDB-ID: #VU48172

Risk: Medium

CVSSv3.1: 8.4 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:H/RL:O/RC:C]

CVE-ID: CVE-2020-27932

CWE-ID: CWE-843 - Type confusion

Exploit availability: Yes

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to a type confusion error in macOS kernel. A local user can run a specially crafted application to trigger a type confusion error and execute arbitrary code with elevated privileges.

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

Mitigation

Install updates from vendor's website.

Vulnerable software versions

macOS: 10.15 19A583 - 10.15.7 19H2

External links

http://support.apple.com/en-us/HT211947

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.

3) Out-of-bounds read

EUVDB-ID: #VU48173

Risk: Low

CVSSv3.1: 6.2 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N/E:H/RL:O/RC:C]

CVE-ID: CVE-2020-27950

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: Yes

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition within macOS kernel. A local user can run a specially crafted program to gain access to sensitive kernel information on the system.

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

Mitigation

Install updates from vendor's website.

Vulnerable software versions

macOS: 10.15 19A583 - 10.15.7 19H2

External links

http://support.apple.com/en-us/HT211947

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

Yes. This vulnerability is being exploited in the wild.

4) Buffer overflow

EUVDB-ID: #VU50216

Risk: Low

CVSSv3.1: 7.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2020-27904

CWE-ID: CWE-119 - Memory corruption

Exploit availability: Yes

Description

The vulnerability allows a local application to escalate privileges on the system.

The vulnerability exists due to a boundary error within the OS kernel subsystem. A local application can execute arbitrary code with kernel privileges.

Mitigation

Install updates from vendor's website.

Vulnerable software versions

macOS: 11.0 20A2411

External links

http://seclists.org/fulldisclosure/2020/Dec/32
http://support.apple.com/en-us/HT211931
http://support.apple.com/kb/HT212147

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.