Apple tvOS up to 16.3.3 FontParser memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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5.0$0-$5k0.00

Summaryinfo

A vulnerability classified as problematic has been found in Apple tvOS up to 16.3.3. The impacted element is an unknown function of the component FontParser. The manipulation leads to memory corruption. This vulnerability is listed as CVE-2023-27956. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in Apple tvOS up to 16.3.3 (Digital Media Player). This issue affects some unknown processing of the component FontParser. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to 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. Impacted is confidentiality. The summary by CVE is:

The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.3, iOS 16.4 and iPadOS 16.4, iOS 15.7.4 and iPadOS 15.7.4, tvOS 16.4, watchOS 9.4. Processing a maliciously crafted image may result in disclosure of process memory.

The weakness was presented 03/27/2023 by Ye Zhang as HT213674 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. The identification of this vulnerability is CVE-2023-27956. It demands that the victim is doing some kind of user interaction. The technical details are unknown and an exploit is not publicly available. The advisory points out:

Processing a maliciously crafted image may result in disclosure of process memory

Upgrading to version 16.4 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

The issue was addressed with improved memory handling.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-31682). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.1
VulDB Meta Temp Score: 5.0

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.5
NVD Vector: 🔍

CNA Base Score: 5.5
CNA Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: tvOS 16.4

Timelineinfo

03/08/2023 🔍
03/27/2023 +18 days 🔍
03/27/2023 +0 days 🔍
03/29/2023 +2 days 🔍
11/30/2025 +977 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT213674
Researcher: Ye Zhang
Status: Confirmed

CVE: CVE-2023-27956 (🔍)
GCVE (CVE): GCVE-0-2023-27956
GCVE (VulDB): GCVE-100-224363
EUVD: 🔍

Entryinfo

Created: 03/29/2023 13:39
Updated: 11/30/2025 05:05
Changes: 03/29/2023 13:39 (19), 03/29/2023 13:42 (27), 04/19/2023 08:30 (1), 12/12/2024 16:40 (27), 01/29/2025 17:14 (11), 04/27/2025 15:19 (3), 11/30/2025 05:05 (1)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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