CVE-2021-1738

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2021-04-02 · updated 2026-06-17
Weakness: CWE-787

Description

An out-of-bounds write was addressed with improved input validation. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave. Processing a maliciously crafted image may lead to arbitrary code execution.

Affected products

Apple iPadOS: before 14.4 — fixed in 14.4
Apple Iphone Os: before 14.4 — fixed in 14.4
macOS: from 10.14 before 10.14.6; from 10.15 before 10.15.7; 10.14.6, 10.14.6-security_update_2019-001, 10.14.6-security_update_2019-002, 10.14.6-security_update_2019-006, 10.14.6-security_update_2019-007, 10.14.6-security_update_2020-001 (+11) — fixed in 10.14.6, 10.15.7
Apple macOS: from 11.0 before 11.2 — fixed in 11.2

How to fix

Upgrade to a fixed version: Apple iPadOS 14.4; Apple Iphone Os 14.4; macOS 10.14.6, 10.15.7; Apple macOS 11.2. Check the vendor advisory for mitigations.

References

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