CVEs / CVE-2021-30952
CVE-2021-30952: Apple Multiple Products Integer Overflow or Wraparound Vulnerability
- Known exploited in the CISA KEV catalog since 5 Mar 2026
- high 7.8 CVSS 3.1 (NVD)
- EPSS 6.96% chance of exploitation in the next 30 days, higher than 94% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Apple tvOS, macOS, Safari, iPadOS and watchOS contain an integer overflow or wraparound vulnerability due to the processing of maliciously crafted web content that may lead to arbitrary code execution.
Description
An integer overflow was addressed with improved input validation. This issue is fixed in tvOS 15.2, macOS Monterey 12.1, Safari 15.2, iOS 15.2 and iPadOS 15.2, watchOS 8.3. Processing maliciously crafted web content may lead to arbitrary code execution.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Apple watchOS | from unspecified, before 8.3 | 8.3 |
| Apple iOS and iPadOS | from unspecified, before 15.2 | 15.2 |
| Apple macOS | from unspecified, before 12.1 | 12.1 |
| Apple macOS | from unspecified, before 15.2 | 15.2 |
Exploitation
| In CISA KEV since | 5 Mar 2026 |
|---|---|
| Due date for US federal agencies | 26 Mar 2026 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable. |
Severity
| CVSS 3.1 | 7.8 highCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HScored by NVD |
|---|---|
| Weakness | CWE-190 |
References
- CVE-2021-30952 on NVD
- CVE-2021-30952 in the CISA KEV catalog
- https://support.apple.com/en-us/HT212975 (cited by CISA)
- https://support.apple.com/en-us/HT212976 (cited by CISA)
- https://support.apple.com/en-us/HT212978 (cited by CISA)
- https://support.apple.com/en-us/HT212980 (cited by CISA)
- https://support.apple.com/en-us/HT212982 (cited by CISA)
- CVE-2021-30952 on OSV
- http://www.openwall.com/lists/oss-security/2022/01/21/2 Mailing List, Third Party Advisory
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/7EQVZ3CEMTINLBZ7PBC7WRXVEVCRHNSM/ Broken Link
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/HQKWD4BXRDD2YGR5AVU7H5J5PIQIEU6V/ Broken Link
- https://support.apple.com/en-us/HT212975 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212976 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212978 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212980 Release Notes, Vendor Advisory
- https://support.apple.com/en-us/HT212982 Release Notes, Vendor Advisory
- https://www.debian.org/security/2022/dsa-5060 Mailing List, Third Party Advisory
- https://www.debian.org/security/2022/dsa-5061 Mailing List, Third Party Advisory
- https://cloud.google.com/blog/topics/threat-intelligence/coruna-powerful-ios-exploit-kit Exploit, Third Party Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30952 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.