high
7.8
CWE
20 125
Advisory Published
CVE Published
Updated

CVE-2021-1881: Input Validation

First published: Mon Apr 26 2021(Updated: )

An out-of-bounds read was addressed with improved input validation. This issue is fixed in Security Update 2021-002 Catalina, Security Update 2021-003 Mojave, iOS 14.5 and iPadOS 14.5, watchOS 7.4, tvOS 14.5, macOS Big Sur 11.3. Processing a maliciously crafted font file may lead to arbitrary code execution.

Credit: Hou JingYi @hjy79425575 Qihoo 360an anonymous researcher Xingwei Lin Ant Security Light Mickey Jin Trend Microan anonymous researcher Ant Security Light Qihoo 360 product-security@apple.com

Affected SoftwareAffected VersionHow to fix
Apple macOS<11.3
11.3
tvOS<14.5
14.5
macOS Catalina
macOS Mojave
Apple iOS, iPadOS, and watchOS<14.5
14.5
Apple iOS, iPadOS, and watchOS<14.5
14.5
Apple iOS, iPadOS, and watchOS<7.4
7.4
Apple iOS, iPadOS, and watchOS<14.5
iOS<14.5
Apple iOS and macOS>=10.14<=10.14.5
Apple iOS and macOS>=10.15<=10.15.5
Apple iOS and macOS=10.14.6
Apple iOS and macOS=10.14.6-security_update_2019-001
Apple iOS and macOS=10.14.6-security_update_2019-002
Apple iOS and macOS=10.14.6-security_update_2019-004
Apple iOS and macOS=10.14.6-security_update_2019-005
Apple iOS and macOS=10.14.6-security_update_2019-006
Apple iOS and macOS=10.14.6-security_update_2019-007
Apple iOS and macOS=10.14.6-security_update_2020-001
Apple iOS and macOS=10.14.6-security_update_2020-002
Apple iOS and macOS=10.14.6-security_update_2020-003
Apple iOS and macOS=10.14.6-security_update_2020-004
Apple iOS and macOS=10.14.6-security_update_2020-005
Apple iOS and macOS=10.14.6-security_update_2020-006
Apple iOS and macOS=10.14.6-security_update_2020-007
Apple iOS and macOS=10.14.6-security_update_2021-001
Apple iOS and macOS=10.14.6-security_update_2021-002
Apple iOS and macOS=10.14.6-supplemental_update
Apple iOS and macOS=10.14.6-supplemental_update_2
Apple iOS and macOS=10.15.6
Apple iOS and macOS=10.15.6-supplemental_update
Apple iOS and macOS=10.15.7
Apple iOS and macOS=10.15.7-security_update_2020
Apple iOS and macOS=10.15.7-security_update_2020-001
Apple iOS and macOS=10.15.7-security_update_2020-005
Apple iOS and macOS=10.15.7-security_update_2020-007
Apple iOS and macOS=10.15.7-security_update_2021-001
Apple iOS and macOS=10.15.7-supplemental_update
Apple iOS and macOS>=11.0<11.3
tvOS<14.5
Apple iOS, iPadOS, and watchOS<7.4

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Peer vulnerabilities

(Found alongside the following vulnerabilities)

Frequently Asked Questions

  • What is CVE-2021-1881?

    CVE-2021-1881 is a vulnerability in Apple's FontParser that allows an attacker to read out-of-bounds memory due to inadequate input validation.

  • What is the severity of CVE-2021-1881?

    The severity of CVE-2021-1881 is not mentioned in the provided information.

  • Which software versions are affected by CVE-2021-1881?

    Affected software versions include Apple iOS up to version 14.5, Apple iPadOS up to version 14.5, Apple watchOS up to version 7.4, Apple macOS Big Sur up to version 11.3, Apple Catalina, Apple tvOS up to version 14.5, and Apple Mojave.

  • How can I fix CVE-2021-1881?

    To fix CVE-2021-1881, apply the recommended updates provided by Apple for the affected software versions.

  • Where can I find more information about CVE-2021-1881?

    You can find more information about CVE-2021-1881 on Apple's official support page with the reference links: [https://support.apple.com/en-us/HT212326](https://support.apple.com/en-us/HT212326), [https://support.apple.com/en-us/HT212327](https://support.apple.com/en-us/HT212327), and [https://support.apple.com/en-us/HT212317](https://support.apple.com/en-us/HT212317).

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