CVE-2025-43300
Apple iOS, iPadOS, and macOS Out-of-Bounds Write Vulnerability
Apple iOS, iPadOS, and macOS
An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS 15.8.5, iOS 16.7.12 and iPadOS 16.7.12, iOS 18.6.2 and iPadOS 18.6.2, iPadOS 17.7.10, macOS Sequoia 15.6.1, macOS Sonoma 14.7.8, macOS Ventura 13.7.8. Processing a malicious image file may result in memory corruption. Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals.
Exploitation status
CISA Known Exploited Vulnerabilities
Listed by CISA on 21 August 2025. US federal agencies were required to remediate it by 11 September 2025.
EPSS — exploitation probability
FIRST puts the probability of exploitation activity in the next 30 days at 32.5%, which is higher than 98.3% 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:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
Frequently asked questions
Is CVE-2025-43300 being exploited by ransomware groups?
No ransomware group in this database is currently recorded as exploiting CVE-2025-43300.
What does CVE-2025-43300 affect?
CVE-2025-43300 affects Apple iOS, iPadOS, and macOS. An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 15.8.5 and iPadOS 15.8.5, iOS 16.7.12 and iPadOS 16.7.12, iOS 18.6.2 and iPadOS 18.6.2, iPadOS 17.7.10, macOS Sequoia 15.6.1, macOS Sonoma 14.7.8, macOS Ventura 13.7.8. Processing a malicious image file may result in memory corruption. Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals.
How severe is CVE-2025-43300?
CVE-2025-43300 is rated CRITICAL with a CVSS base score of 10. EPSS puts the probability of exploitation in the next 30 days at 32.5%, higher than 98.3% of all scored vulnerabilities. It is listed in the CISA Known Exploited Vulnerabilities catalog, with a federal remediation deadline of 11 September 2025.
How should organisations respond to CVE-2025-43300?
Apply the vendor patch for Apple iOS, iPadOS, and macOS 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.