Apple iOS/iPadOS up to 15.1.1 WebKit race condition

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability classified as critical has been found in Apple iOS and iPadOS up to 15.1.1. This impacts an unknown function of the component WebKit. This manipulation causes race condition. This vulnerability appears as CVE-2021-30984. The attack may be initiated remotely. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in Apple iOS and iPadOS up to 15.1.1 (Smartphone Operating System). It has been declared as critical. Affected by this vulnerability is some unknown processing of the component WebKit. The manipulation with an unknown input leads to a race condition vulnerability. The CWE definition for the vulnerability is CWE-362. The product contains a code sequence that can run concurrently with other code, and the code sequence requires temporary, exclusive access to a shared resource, but a timing window exists in which the shared resource can be modified by another code sequence that is operating concurrently. As an impact it is known to affect confidentiality, integrity, and availability.

The weakness was presented 12/13/2021 with Kunlun Lab as HT212976 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known as CVE-2021-30984. 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 $0-$5k 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 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:

A race condition was addressed with improved state handling.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-0631). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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: Race condition
CWE: CWE-362
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
Organization: Kunlun Lab
Status: Confirmed

CVE: CVE-2021-30984 (🔍)
GCVE (CVE): GCVE-0-2021-30984
GCVE (VulDB): GCVE-100-188593
CERT Bund: WID-SEC-2026-0631 - Apple macOS: Mehrere Schwachstellen

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

Entryinfo

Created: 12/17/2021 16:52
Updated: 03/08/2026 11:53
Changes: 12/17/2021 16:52 (4), 12/17/2021 16:53 (15), 12/17/2021 16:56 (28), 12/23/2021 12:17 (1), 03/08/2026 11:53 (21)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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