Apple iOS/iPadOS up to 15.1.1 WebKit out-of-bounds

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$5k-$25k0.00

Summaryinfo

A vulnerability classified as critical was found in Apple iOS and iPadOS up to 15.1.1. Affected is an unknown function of the component WebKit. Such manipulation leads to out-of-bounds. This vulnerability is traded as CVE-2021-30953. The attack may be launched remotely. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Apple iOS and iPadOS up to 15.1.1 (Smartphone Operating System). It has been rated as critical. Affected by this issue is an unknown function of the component WebKit. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability.

The weakness was shared 12/13/2021 by VRIJ as HT212976 as confirmed advisory (Website). The advisory is available at support.apple.com. This vulnerability is handled as CVE-2021-30953. 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 03/07/2026). 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

Upgrading to version 15.2 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

An out-of-bounds read was addressed with improved bounds checking.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0631). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Affected

  • Apple macOS

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: Out-of-bounds
CWE: CWE-125 / 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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: iOS/iPadOS 15.2

Timelineinfo

04/13/2021 🔍
12/13/2021 +244 days 🔍
12/13/2021 +0 days 🔍
12/17/2021 +4 days 🔍
03/07/2026 +1541 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212976
Researcher: VRIJ
Status: Confirmed

CVE: CVE-2021-30953 (🔍)
GCVE (CVE): GCVE-0-2021-30953
GCVE (VulDB): GCVE-100-188594
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 12/17/2021 16:53
Updated: 03/07/2026 14:22
Changes: 12/17/2021 16:53 (19), 12/17/2021 16:56 (28), 12/23/2021 12:24 (1), 03/07/2026 14:22 (21)
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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