CVE-2021-30665
Out-of-bounds Write
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Description
A memory corruption issue was addressed with improved state management. This issue is fixed in watchOS 7.4.1, iOS 14.5.1 and iPadOS 14.5.1, tvOS 14.6, iOS 12.5.3, macOS Big Sur 11.3.1. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..
Official description from the CVE record, published by apple. Copyright © 1999-2026 The MITRE Corporation. See /security/cve/legal for the CVE license. View the record on cve.org
Key data
CVSS 3.1 High 8.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector: Network
The vulnerable component can be reached over a network, possibly from the Internet.
Attack complexity: Low
No special conditions are needed. The attack can be repeated at will.
Privileges required: None
No account or privileges are needed.
User interaction: Required
A user has to do something first, such as opening a file or following a link.
Scope: Unchanged
The impact stays within the vulnerable component.
Confidentiality impact: High
Serious or total effect on the secrecy of data.
Integrity impact: High
Serious or total effect on the trustworthiness of data.
Availability impact: High
Serious or total effect on availability.
| Metric | Value | What it means |
|---|---|---|
| Attack vector | Network | The vulnerable component can be reached over a network, possibly from the Internet. |
| Attack complexity | Low | No special conditions are needed. The attack can be repeated at will. |
| Privileges required | None | No account or privileges are needed. |
| User interaction | Required | A user has to do something first, such as opening a file or following a link. |
| Scope | Unchanged | The impact stays within the vulnerable component. |
| Confidentiality impact | High | Serious or total effect on the secrecy of data. |
| Integrity impact | High | Serious or total effect on the trustworthiness of data. |
| Availability impact | High | Serious or total effect on availability. |
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EPSS
- Score
- 0.03706 (3.7% probability)
- Percentile
- 89.8%
- Scores of
- Nov 10, 2026
- Model
- v2026.06.15
CISA Known Exploited Vulnerabilities
- Name in the catalog
- Apple Multiple Products WebKit Memory Corruption Vulnerability
- Added to the catalog
- Nov 3, 2021
- Federal due date
- Nov 17, 2021
CISA assessment as of Jan 29, 2025
- Exploitation
- Recorded by CISA as active
- Automatable
- no
- Technical impact
- total
Weakness (CWE)
- CWE-787Out-of-bounds Write
Affected products
Apple macOS
- affected: unspecified up to before 11.3
Apple macOS
- affected: unspecified up to before 14.5
Apple macOS
- affected: unspecified up to before 7.4
Apple macOS
- affected: unspecified up to before 12.5
Apple macOS
- affected: unspecified up to before 14.6
References
Timeline
- ID reserved
- Record published
- Added to CISA KEV
- Record last updated
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About CubePath
Data from the CVE Program (MITRE), CISA KEV and FIRST EPSS. CVSS is owned by FIRST and used by permission. Not affiliated with or endorsed by MITRE, CISA or FIRST. Data as of Nov 10, 2026, 19:51 UTC. Sources and licenses