Apple iOS/iPadOS up to 14.6 libxml2 use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$5k-$25k0.00

Summaryinfo

A vulnerability was found in Apple iOS and iPadOS up to 14.6 and classified as critical. Affected by this vulnerability is an unknown functionality of the component libxml2. Such manipulation leads to an unknown weakness. This vulnerability is listed as CVE-2021-3518. The attack may be performed from remote. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Apple iOS and iPadOS up to 14.6 (Smartphone Operating System). Affected by this issue is an unknown code of the component libxml2. Using CWE to declare the problem leads to CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. Impacted is confidentiality, integrity, and availability.

The weakness was presented 07/19/2021 as HT212601 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is handled as CVE-2021-3518. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 05/16/2025). It is expected to see the exploit prices for this product increasing in the near future. 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

Type

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: iOS/iPadOS 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: HT212601
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2021-3518 (🔍)
GCVE (CVE): GCVE-0-2021-3518
GCVE (VulDB): GCVE-100-179498
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 07/23/2021 08:19
Updated: 05/16/2025 05:04
Changes: 07/23/2021 08:19 (17), 07/23/2021 08:22 (28), 07/27/2021 17:35 (3), 07/27/2021 17:43 (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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