Apple iOS/iPadOS up to 15.1.1 Model I/O out-of-bounds write

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 was found in Apple iOS and iPadOS up to 15.1.1. It has been rated as critical. Affected by this vulnerability is an unknown functionality of the component Model I/O. The manipulation leads to out-of-bounds write. This vulnerability is listed as CVE-2021-30971. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in Apple iOS and iPadOS up to 15.1.1 (Smartphone Operating System) and classified as critical. This issue affects an unknown function of the component Model I/O. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability.

The weakness was presented 12/13/2021 by Ye Zhang as HT212976 as confirmed advisory (Website). The advisory is shared at support.apple.com. The identification of this vulnerability is CVE-2021-30971. 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 03/08/2026). It is expected to see the exploit prices for this product increasing in the near future. The advisory points out:

Processing a maliciously crafted USD file may lead to unexpected application termination or 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 write issue 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 the best quality for vulnerability data then you always have to consider 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 write
CWE: CWE-787 / 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 🔍
03/08/2026 +1542 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212976
Researcher: Ye Zhang
Status: Confirmed

CVE: CVE-2021-30971 (🔍)
GCVE (CVE): GCVE-0-2021-30971
GCVE (VulDB): GCVE-100-188573
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

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

Entryinfo

Created: 12/17/2021 16:45
Updated: 03/08/2026 10:49
Changes: 12/17/2021 16:45 (11), 12/17/2021 16:46 (8), 12/17/2021 16:49 (28), 12/23/2021 10:04 (1), 03/08/2026 10:49 (21)
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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