Apple tvOS up to 14.6 libxml2 use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple tvOS up to 14.6. Affected is an unknown function of the component libxml2. Executing a manipulation can lead to an unknown weakness. This vulnerability is registered as CVE-2021-3518. It is possible to launch the attack remotely. No exploit is available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple tvOS up to 14.6 (Digital Media Player). It has been declared as critical. This vulnerability affects an unknown functionality of the component libxml2. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was published 07/19/2021 as HT212604 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability was named CVE-2021-3518. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The advisory points out:

A remote attacker may be able to cause arbitrary code execution

The vulnerability scanner Nessus provides a plugin with the ID 236735 (Alibaba Cloud Linux 3 : 0047: libxml2 (ALINUX3-SA-2021:0047)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 14.7 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

This issue was addressed with improved checks.

The vulnerability is also documented in the vulnerability database at Tenable (236735). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.6
VulDB Meta Temp Score: 7.4

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

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 236735
Nessus Name: Alibaba Cloud Linux 3 : 0047: libxml2 (ALINUX3-SA-2021:0047)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: tvOS 14.7

Timelineinfo

04/27/2021 🔍
07/19/2021 +83 days 🔍
07/19/2021 +0 days 🔍
07/23/2021 +4 days 🔍
05/16/2025 +1393 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212604
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-3518 (🔍)
GCVE (CVE): GCVE-0-2021-3518
GCVE (VulDB): GCVE-100-179530

Entryinfo

Created: 07/23/2021 08:54
Updated: 05/16/2025 05:04
Changes: 07/23/2021 08:54 (17), 07/23/2021 08:57 (27), 07/28/2021 07:55 (3), 07/28/2021 08:02 (19), 05/16/2025 05:04 (17)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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