Apple watchOS up to 9.4 WebKit out-of-bounds

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
5.7	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Apple watchOS up to 9.4. The impacted element is an unknown function of the component WebKit. Executing a manipulation can lead to out-of-bounds. This vulnerability appears as CVE-2023-28204. The attack may be performed from remote. In addition, an exploit is available. You should upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple watchOS up to 9.4 (Smartwatch Operating System). It has been declared as problematic. This vulnerability affects some unknown functionality of the component WebKit. The manipulation with an unknown input leads to a out-of-bounds vulnerability. The CWE definition for the vulnerability is CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality. CVE summarizes:

An out-of-bounds read was addressed with improved input validation. This issue is fixed in watchOS 9.5, tvOS 16.5, macOS Ventura 13.4, iOS 15.7.6 and iPadOS 15.7.6, Safari 16.5, iOS 16.5 and iPadOS 16.5. Processing web content may disclose sensitive information. Apple is aware of a report that this issue may have been actively exploited.

The weakness was presented 05/18/2023 as HT213764 as confirmed advisory (Website). The advisory is shared for download at support.apple.com. This vulnerability was named CVE-2023-28204. Successful exploitation requires user interaction by the victim. Technical details are unknown but an exploit is available. The advisory points out:

Processing web content may disclose sensitive information. Apple is aware of a report that this issue may have been actively exploited.

It is declared as attacked. The vulnerability scanner Nessus provides a plugin with the ID 212173 (Apple Safari 16.5 Multiple Vulnerabilities (102735)), which helps to determine the existence of the flaw in a target environment. This issue was added on 05/22/2023 to the CISA Known Exploited Vulnerabilities Catalog with a due date of 06/12/2023:

Apply updates per vendor instructions.

Upgrading to version 9.5 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 read was addressed with improved input validation.

The vulnerability is also documented in the databases at Zero-Day.cz (768), Tenable (212173) and EUVD (EUVD-2023-31912). Once again VulDB remains the best source for vulnerability data.

Productinfo

Type

Smartwatch Operating System

Vendor

Apple

Name

watchOS

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: 5.8
VulDB Meta Temp Score: 5.7

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

NVD Base Score: 6.5
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Nessus ID: 212173
Nessus Name: Apple Safari 16.5 Multiple Vulnerabilities (102735)

Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: watchOS 9.5

Timelineinfo

03/13/2023 🔍
05/18/2023 +65 days 🔍
05/18/2023 +0 days 🔍
05/20/2023 +2 days 🔍
12/03/2025 +928 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT213764
Status: Confirmed

CVE: CVE-2023-28204 (🔍)
GCVE (CVE): GCVE-0-2023-28204
GCVE (VulDB): GCVE-100-229588
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/20/2023 08:36
Updated: 12/03/2025 18:26
Changes: 05/20/2023 08:36 (18), 05/20/2023 08:40 (28), 06/15/2023 11:01 (1), 04/28/2024 18:05 (23), 05/15/2024 17:15 (1), 06/12/2024 01:36 (2), 06/28/2024 02:28 (12), 09/09/2024 22:30 (2), 12/09/2024 18:44 (2), 02/03/2025 23:43 (11), 04/26/2025 15:00 (3), 12/03/2025 18:26 (1)
Complete: 🔍
Cache ID: 216::103