Apple watchOS up to 5.3.8/6.2.8/7.0.3 FontParser memory corruption

Summaryinfo

A vulnerability classified as critical was found in Apple watchOS up to 5.3.8/6.2.8/7.0.3. Affected is an unknown function of the component FontParser. Executing a manipulation can lead to memory corruption. This vulnerability is handled as CVE-2020-27930. The attack can be executed remotely. Additionally, an exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Apple watchOS up to 5.3.8/6.2.8/7.0.3 (Smartwatch Operating System) and classified as critical. This vulnerability affects an unknown function of the component FontParser. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A memory corruption issue was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.1, iOS 12.4.9, watchOS 6.2.9, Security Update 2020-006 High Sierra, Security Update 2020-006 Mojave, iOS 14.2 and iPadOS 14.2, watchOS 5.3.9, macOS Catalina 10.15.7 Supplemental Update, macOS Catalina 10.15.7 Update. Processing a maliciously crafted font may lead to arbitrary code execution.

The weakness was released 11/05/2020 with Google Project Zero as HT211928 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability was named CVE-2020-27930. 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. Technical details are unknown but an exploit is available. The advisory points out:

Processing a maliciously crafted font may lead to arbitrary code execution. Apple is aware of reports that an exploit for this issue exists in the wild.

It is declared as attacked. This issue was added on 11/03/2021 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 05/03/2022:

Apply updates per vendor instructions.

Upgrading to version 5.3.9, 6.2.9 or 7.1 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A memory corruption issue was addressed with improved input validation.

The vulnerability is also documented in the vulnerability database at Zero-Day.cz (590). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Type

• Smartwatch Operating System

Vendor

• Apple

Name

• watchOS

Version

• 5.3.0
• 5.3.1
• 5.3.2
• 5.3.3
• 5.3.4
• 5.3.5
• 5.3.6
• 5.3.7
• 5.3.8
• 6.2.0
• 6.2.1
• 6.2.2
• 6.2.3
• 6.2.4
• 6.2.5
• 6.2.6
• 6.2.7
• 6.2.8
• 7.0.0
• 7.0.1
• 7.0.2
• 7.0.3

License

• commercial

Website

• Vendor: https://www.apple.com/

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VulDB is the best source for vulnerability data and more expert information about this specific topic.

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