What is CVE-2021-30749?

CVE-2021-30749 is a high-severity vulnerability in Apple iOS And Ipados, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-09-08.

How severe is CVE-2021-30749?

High severity. CVSS v3 base score is 8.8 out of 10.

Buffer overflow in Apple iOS And Ipados

CVE-2021-30749

Multiple memory corruption issues were addressed with improved memory handling. This issue is fixed in tvOS 14.6, iOS 14.6 and iPadOS 14.6, Safari 14.1.1, macOS Big Sur 11.4, watchOS 7.5. Processing maliciously crafted web content may lead to arbitrary code execution.

Vulnerability class: Buffer Overflow

Published 2021-09-08 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.017 (76.0th percentile), scored 2026-10-02.

Low probability of exploitation in the next 30 days, but still tracked. 76th percentile — 76.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.017 · newest: 0.017 · change: 0.000

Affected products

Apple iOS And Ipados — versions unspecified
Apple Ipados
Apple Iphone OS
Apple macOS — versions unspecified
Apple Safari
Apple tvOS
Apple watchOS

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

support.apple.com/en-us/HT212528 (Vendor Advisory)
support.apple.com/en-us/HT212529 (Vendor Advisory)
support.apple.com/en-us/HT212532 (Vendor Advisory)
support.apple.com/en-us/HT212533 (Vendor Advisory)
support.apple.com/en-us/HT212534 (Vendor Advisory)

Frequently asked questions

What is CVE-2021-30749?: CVE-2021-30749 is a high-severity vulnerability in Apple iOS And Ipados, classified under Out-of-bounds Write. CVSS score: 8.8/10. Published 2021-09-08.
How severe is CVE-2021-30749?: High severity. CVSS v3 base score is 8.8 out of 10.