Vulnerability · CVE-2021-30900
Apple iOS, iPadOS, and macOS Out-of-Bounds Write Vulnerability
Published Aug 24, 2021 · catalog updated Jun 16, 2026 · Apple iOS, iPadOS, and macOS
Patch now
CVE-2021-30900 is in the CISA known-exploited catalog, due Apr 20, 2023. Confirm Apple iOS, iPadOS, and macOS against the vendor advisory and apply that fix. The CVSS score does not change the priority.
- Severity
- High7.8
- Known exploitation
- CISA KEV and VulnCheck KEV
- EPSS
- 5.20%
- Remediation
- Remediation guidance
- Affected products
- cpe apple/ipados · cpe apple/iphone os · cpe apple/macos · vendor Apple iOS, iPadOS, and macOS
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. A malicious application may be able to execute arbitrary code with kernel privileges.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe apple/ipados15.0
- cpe apple/iphone os15.0
- cpe apple/macosversion unspecified
- vendor Apple iOS, iPadOS, and macOSversion unspecified
How to fix CVE-2021-30900
Recommended remediation
Apply updates per vendor instructions. CISA due date Apr 20, 2023.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
CVE-2021-30900 is in the CISA known-exploited catalog, due Apr 20, 2023. Confirm Apple iOS, iPadOS, and macOS against the vendor advisory and apply that fix. The CVSS score does not change the priority.
Which versions are affected?
Compare what you have installed with apple/iphone os 15.0. Apply updates per vendor instructions.
What should an analyst verify?
CWE-20: Improper Input Validation; CWE-787: Out-of-bounds Write. EPSS 5.20%. The CISA KEV listing is the exploitation evidence. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Aug 24, 2021 · Catalog
Detected
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. A malicious application may be able to execute arbitrary code with kernel privileges.
Mar 30, 2023 · CISA KEV
Known exploited
Apply updates per vendor instructions.
Apr 20, 2023 · CISA KEV
Remediation due
Apply updates per vendor instructions.
Jun 16, 2026 · Catalog
Updated
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. A malicious application may be able to execute arbitrary code with kernel privileges.
Sources
- CISA KEVConfirmed exploitationCVE-2021-30900
Apple GPU drivers, included in iOS, iPadOS, and macOS, contain an out-of-bounds write vulnerability that may allow a malicious application to execute code with kernel privileges.
cisa.gov - CVE.orgVulnerability recordCVE-2021-30900
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2021-30900
30-day exploitation probability 5.2%
first.org - NIST NVDVulnerability recordCVE-2021-30900
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.8.1 and iPadOS 14.8.1, iOS 15.1 and iPadOS 15.1. A malicious application may be able to execute arbitrary code with kernel privileges.
nvd.nist.gov - VulnCheck KEVConfirmed exploitationCVE-2021-30900
Apple GPU drivers, included in iOS, iPadOS, and macOS, contain an out-of-bounds write vulnerability that may allow a malicious application to execute code with kernel privileges.
vulncheck.com
References
Freshness
Last verified in this catalog Oct 17, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.