Apple tvOS up to 14.4 WebKit Storage use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.9$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as critical, has been found in Apple tvOS up to 14.4. Affected is an unknown function of the component WebKit Storage. Performing a manipulation results in use after free. This vulnerability was named CVE-2021-30661. The attack may be initiated remotely. In addition, an exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Apple tvOS up to 14.4 (Digital Media Player). This affects an unknown functionality of the component WebKit Storage. The manipulation with an unknown input leads to a use after free vulnerability. CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A use after free issue was addressed with improved memory management. This issue is fixed in Safari 14.1, iOS 12.5.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..

The weakness was presented 04/26/2021 by yangkang as HT212323 as confirmed advisory (Website). It is possible to read the advisory at support.apple.com. This vulnerability is uniquely identified as CVE-2021-30661. It demands that the victim is doing some kind of user interaction. Technical details are unknown but a private exploit is available. The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution. 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 223935 (Linux Distros Unpatched Vulnerability : CVE-2021-30661), which helps to determine the existence of the flaw in a target environment. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

Upgrading to version 14.5 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

A use after free issue was addressed with improved memory management.

The vulnerability is also documented in the databases at Zero-Day.cz (624), Tenable (223935) and EUVD (EUVD-2021-17578). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.9

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

NVD Base Score: 8.8
NVD Vector: 🔍

CNA Base Score: 8.8
CNA Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Private
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

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

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 223935
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2021-30661

Zero-Day.cz: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: tvOS 14.5

Timelineinfo

04/13/2021 🔍
04/26/2021 +13 days 🔍
04/26/2021 +0 days 🔍
04/27/2021 +1 days 🔍
07/29/2025 +1554 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212323
Researcher: yangkang
Status: Confirmed

CVE: CVE-2021-30661 (🔍)
GCVE (CVE): GCVE-0-2021-30661
GCVE (VulDB): GCVE-100-174063
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 04/27/2021 11:00
Updated: 07/29/2025 06:02
Changes: 04/27/2021 11:00 (17), 04/27/2021 11:01 (2), 04/27/2021 11:04 (29), 05/01/2021 10:15 (1), 04/21/2024 15:11 (23), 05/15/2024 17:15 (2), 06/29/2024 03:51 (2), 09/14/2024 00:06 (1), 01/30/2025 02:48 (29), 03/05/2025 11:00 (2), 05/03/2025 21:58 (3), 07/29/2025 06:02 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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