Apple tvOS up to 14.1 FontParser out-of-bounds write

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6.0	$0-$5k	0.00

Summaryinfo

A vulnerability labeled as critical has been found in Apple tvOS up to 14.1. This vulnerability affects unknown code of the component FontParser. Executing a manipulation can lead to out-of-bounds write. This vulnerability appears as CVE-2020-27927. The attack may be performed from remote. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Apple tvOS up to 14.1 (Digital Media Player) and classified as critical. This vulnerability affects an unknown part of the component FontParser. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 11/05/2020 by Xingwei Lin as HT211930 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability was named CVE-2020-27927. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The advisory points out:

Processing a maliciously crafted font file may lead to arbitrary code execution

Upgrading to version 14.2 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

An out-of-bounds write issue was addressed with improved bounds checking.

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Productinfo

Type

Digital Media Player

Vendor

Apple

Name

tvOS

Version

License

commercial

Website

Vendor: https://www.apple.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: tvOS 14.2

Timelineinfo

10/27/2020 🔍
11/05/2020 +9 days 🔍
11/05/2020 +0 days 🔍
11/06/2020 +1 days 🔍
12/03/2020 +27 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT211930
Researcher: Xingwei Lin
Status: Confirmed

CVE: CVE-2020-27927 (🔍)
GCVE (CVE): GCVE-0-2020-27927
GCVE (VulDB): GCVE-100-164398

Entryinfo

Created: 11/06/2020 08:49
Updated: 12/03/2020 06:41
Changes: 11/06/2020 08:49 (11), 11/06/2020 08:50 (7), 11/06/2020 08:53 (28), 12/03/2020 06:41 (1)
Complete: 🔍
Cache ID: 216::103