CVE-2021-30952
Apple Multiple Products Integer Overflow or Wraparound Vulnerability
Apple Multiple Products
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.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 5 March 2026. US federal agencies were required to remediate it by 26 March 2026.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 7%, which is higher than 94.2% of all scored vulnerabilities. EPSS is a forecast of activity, not a measure of severity, and it is rescored daily.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Frequently asked questions
Is CVE-2021-30952 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2021-30952.
What does CVE-2021-30952 affect?
CVE-2021-30952 affects Apple Multiple Products. 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.
How severe is CVE-2021-30952?
CVE-2021-30952 is rated HIGH with a CVSS base score of 7.8. EPSS puts the probability of exploitation in the next 30 days at 7%, higher than 94.2% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 26 March 2026.
How should organisations respond to CVE-2021-30952?
Apply the vendor patch for Apple Multiple Products as the first priority, and treat any internet-facing instance as the most urgent. Because this vulnerability is associated with ransomware activity, also review whether the affected systems were reachable before patching, rather than assuming that patching alone closes the incident.