Apple macOS 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 macOS. Affected by this vulnerability is an unknown functionality of the component libxml2. The manipulation results in an unknown weakness. This vulnerability is identified as CVE-2021-3518. The attack can be executed remotely. There is not any exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Apple macOS (Operating System) (affected version unknown). Affected is an unknown functionality of the component libxml2. 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 weakness was released 07/21/2021 as HT212602 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is traded as 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 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

Type

Vendor

Name

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
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: 🔍

Timelineinfo

04/27/2021 🔍
07/21/2021 +85 days 🔍
07/21/2021 +0 days 🔍
07/23/2021 +2 days 🔍
05/16/2025 +1393 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212602
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-3518 (🔍)
GCVE (CVE): GCVE-0-2021-3518
GCVE (VulDB): GCVE-100-179586
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 07/23/2021 10:26
Updated: 05/16/2025 06:07
Changes: 07/23/2021 10:26 (6), 07/23/2021 10:27 (9), 07/23/2021 10:30 (28), 07/28/2021 11:22 (3), 07/28/2021 11:30 (19), 05/16/2025 06:07 (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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