CVE-2021-30858
Apple iOS, iPadOS, macOS Use-After-Free Vulnerability is confirmed as actively exploited and is listed in the CISA KEV catalog.
Required action
Apply updates per vendor instructions.
CISA notes
https://nvd.nist.gov/vuln/detail/CVE-2021-30858
Description
A use after free issue was addressed with improved memory management. This issue is fixed in iOS 14.8 and iPadOS 14.8, macOS Big Sur 11.6. 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.
Severity
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation Context
as of October 17, 2026- CISA added CVE-2021-30858 to the KEV catalog 71 days after its CVE record was published.
- It is one of 95 Apple entries in the CISA KEV catalog, and one of 23 added in 2021.
- Its current EPSS score (13.4%) is higher than that of 29% of CISA KEV entries.
Affected Products
| Vendor | Product | Affected versions |
|---|---|---|
| Apple | Apple macOS | unspecified to <11.6 |
| Apple | Apple iOS | unspecified to <14.8 |
References
18 Links- 20210917 APPLE-SA-2021-09-13-3 macOS Big Sur 11.6
- 20210917 APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8
- 20210917 APPLE-SA-2021-09-13-5 Safari 14.1.2
- [oss-security] 20210920 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0005
- 20210921 APPLE-SA-2021-09-20-6 Additional information for APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8
- 20210921 APPLE-SA-2021-09-20-7 Additional information for APPLE-SA-2021-09-13-3 macOS Big Sur 11.6
- 20210924 APPLE-SA-2021-09-23-1 iOS 12.5.5
- [oss-security] 20211026 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006
- [oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006
- [oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006
- [oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006
Record Details
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CVE record data © The MITRE Corporation, used under the CVE Terms of Use. Exploited-in-the-wild data from the CISA Known Exploited Vulnerabilities catalog (CC0). Exploit prediction scores by FIRST EPSS (first.org/epss). This site is not endorsed or certified by MITRE, NVD, CISA, or FIRST.