CVEs / CVE-2021-30661
CVE-2021-30661: Apple Multiple Products WebKit Storage Use-After-Free Vulnerability
- Known exploited in the CISA KEV catalog since 3 Nov 2021
- high 8.8 CVSS 3.1 (NVD)
- EPSS 4.49% chance of exploitation in the next 30 days, higher than 91% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Apple iOS, iPadOS, macOS, tvOS, watchOS, and Safari WebKit Storage contain a use-after-free vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.
Description
A use after free issue was addressed with improved memory management. This issue is fixed in Safari 14.1, iOS 12.5.3, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. 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..
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Apple iOS and iPadOS | from unspecified, before 14.5 | 14.5 |
| Apple Safari | from unspecified, before 14.1 | 14.1 |
| Apple tvOS | from unspecified, before 14.5 | 14.5 |
| Apple watchOS | from unspecified, before 7.4 | 7.4 |
| Apple macOS | from unspecified, before 11.3 | 11.3 |
| Apple macOS | from unspecified, before 12.5 | 12.5 |
Exploitation
| In CISA KEV since | 3 Nov 2021 |
|---|---|
| Due date for US federal agencies | 17 Nov 2021 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 8.8 highCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-416 |
References
- CVE-2021-30661 on NVD
- CVE-2021-30661 in the CISA KEV catalog
- CVE-2021-30661 on OSV
- https://support.apple.com/en-us/HT212317 Vendor Advisory
- https://support.apple.com/en-us/HT212318 Vendor Advisory
- https://support.apple.com/en-us/HT212323 Vendor Advisory
- https://support.apple.com/en-us/HT212324 Vendor Advisory
- https://support.apple.com/en-us/HT212325 Vendor Advisory
- https://support.apple.com/en-us/HT212341 Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30661 Third Party Advisory, US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.