Apple iOS/iPadOS up to 14.5.1 WebKit use after free

CVSS Meta Temp Score
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability was found in Apple iOS and iPadOS up to 14.5.1. It has been rated as critical. Affected by this vulnerability is an unknown functionality of the component WebKit. The manipulation leads to use after free. This vulnerability is uniquely identified as CVE-2021-21779. The attack is possible to be carried out remotely. No exploit exists. Upgrading the affected component is advised.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Apple iOS and iPadOS up to 14.5.1 (Smartphone Operating System). This issue affects an unknown function of the component WebKit. The manipulation with an unknown input leads to a use after free vulnerability. 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 disclosed 05/24/2021 by Marcin Towalski as HT212528 as confirmed advisory (Website). The advisory is shared at support.apple.com. The identification of this vulnerability is CVE-2021-21779. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 07/10/2025). It is expected to see the exploit prices for this product increasing in the near future. The advisory points out:

Processing maliciously crafted web content may lead to arbitrary code execution

The vulnerability scanner Nessus provides a plugin with the ID 241427 (RHEL 7 : webkitgtk4 (RHSA-2025:10364)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 14.6 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 vulnerability database at Tenable (241427). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

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

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

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: 241427
Nessus Name: RHEL 7 : webkitgtk4 (RHSA-2025:10364)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: iOS/iPadOS 14.6

Timelineinfo

01/04/2021 🔍
05/24/2021 +139 days 🔍
05/24/2021 +0 days 🔍
05/25/2021 +1 days 🔍
07/10/2025 +1507 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212528
Researcher: Marcin Towalski
Status: Confirmed

CVE: CVE-2021-21779 (🔍)
GCVE (CVE): GCVE-0-2021-21779
GCVE (VulDB): GCVE-100-175637
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 05/25/2021 11:59
Updated: 07/10/2025 13:15
Changes: 05/25/2021 11:59 (19), 05/25/2021 12:02 (28), 05/27/2021 19:27 (4), 07/10/2025 13:15 (16)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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