What is CVE-2020-9897?

CVE-2020-9897 is a high-severity vulnerability in Apple iOS And Ipados, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2021-10-28.

How severe is CVE-2020-9897?

High severity. CVSS v3 base score is 7.8 out of 10.

Is CVE-2020-9897 known to be exploited?

2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

Buffer overflow in Apple iOS And Ipados

CVE-2020-9897

An out-of-bounds write was addressed with improved input validation. This issue is fixed in iOS 14.2 and iPadOS 14.2, macOS Big Sur 11.0.1. Processing a maliciously crafted PDF may lead to arbitrary code execution.

Vulnerability class: Buffer Overflow

Published 2021-10-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.009 (59.5th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 60th percentile — 59.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.009 · newest: 0.009 · change: 0.000

Affected products

Apple iOS And Ipados — versions unspecified
Apple Ipados
Apple Iphone OS
Apple macOS — versions unspecified

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

Public proof-of-concept exploits

References

support.apple.com/en-us/HT211931 (Vendor Advisory)
support.apple.com/en-us/HT211929 (Vendor Advisory)

Frequently asked questions

What is CVE-2020-9897?: CVE-2020-9897 is a high-severity vulnerability in Apple iOS And Ipados, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2021-10-28.
How severe is CVE-2020-9897?: High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2020-9897 known to be exploited?: 2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.