CVE-2021-30759: Input Validation

Published Jul 19, 2021
·
Updated

A stack overflow was addressed with improved input validation. This issue is fixed in iOS 14.7, macOS Big Sur 11.5, watchOS 7.6, tvOS 14.7, Security Update 2021-005 Mojave, Security Update 2021-004 Catalina. Processing a maliciously crafted font file may lead to arbitrary code execution.

Other sources

ActionKit. An input validation issue was addressed with improved input validation.

— Apple

AMD Kernel. A memory corruption issue was addressed with improved input validation.

— Apple

Analytics. A logic issue was addressed with improved restrictions.

— Apple

Analytics. This issue was addressed with a new entitlement.

— Apple

App Store. A permissions issue was addressed with improved validation.

— Apple

Credit

hjy79425575(Trend Micro Zero Day Initiative), Zachary Keffaber@@QuickUpdate5, Denis Tokarev@@illusionofcha0s, tr3e, George Nosenko, JunDong Xie(Ant Security Light), ryuzaki, Mickey Jin@@patch1t(Trend Micro), Sunglin(Knownsec 404 team), Yizhuo Wang(Group of Software Security In Progress), Tim Michaud@@TimGMichaud(Zoom Video Communications), Linus Henze (pinauten.de), Csaba Fitzl@@theevilbit(Offensive Security), tr3e(Trend Micro Zero Day Initiative), Matthew Denton(Google Chrome Security), Jzhu(Baidu Security), Ye Zhang@@co0py_Cat(Baidu Security), CFF(Topsec Alpha Team), CVE-2021-3518, CVE-2018-25010, CVE-2018-25011, CVE-2018-25014, CVE-2020-36328, CVE-2020-36329, CVE-2020-36330, CVE-2020-36331, Anonymous(Trend Micro Zero Day Initiative), Christoph Guttandin(Media Codings), Sergei Glazunov(Google Project Zero), Ivan Fratric(Google Project Zero), vm_call, Nozhdar Abdulkhaleq Shukri, Mickey Jin@@patch1t(Trend Micro working with Trend Micro Zero Day Initiative), Georgi Valkov (httpstorm.com), Zhongcheng Li (CK01), Ron Waisberg@@epsilan, Gary Nield(ECSC Group plc), Wojciech Reguła@@_r3ggi(SecuRing), Matt Shockley (twitter.com/mattshockl)(Offensive Security), Liu Long(Ant Security Light), Yinyi Wu@@3ndy1(Qihoo 360 Vulcan Team), Zuozhi Fan@@pattern_F_(Ant Security TianQiong Lab), ABC Research s.r.o

Affected Software

56 affected componentsFixes available
Apple macOS Big Sur<11.5
11.5
Apple tvOS<14.7
14.7
Apple Catalina
Apple Mojave
Apple WatchOS<7.6
7.6
Apple iPadOS<14.7
Apple iPhone OS<14.7
Apple iOS and macOS=10.14
Apple iOS and macOS=10.14.0
Apple iOS and macOS=10.14.1
Apple iOS and macOS=10.14.2
Apple iOS and macOS=10.14.3
Apple iOS and macOS=10.14.4
Apple iOS and macOS=10.14.5
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-security_update_2021-003
Apple iOS and macOS=10.14.6-security_update_2021-004
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
Apple iOS and macOS=10.15.1
Apple iOS and macOS=10.15.2
Apple iOS and macOS=10.15.3
Apple iOS and macOS=10.15.4
Apple iOS and macOS=10.15.5
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-security_update_2021-002
Apple iOS and macOS=10.15.7-security_update_2021-003
Apple iOS and macOS=10.15.7-supplemental_update
Apple macOS>=11.0<11.5
Apple tvOS<14.7
Apple WatchOS<7.6
Apple iOS<14.7
14.7
Apple iPadOS<14.7
14.7

Event History

Jul 19, 2021
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Updated
via Apple·12:00 AM
Affected Software
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Jul 21, 2021
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
Affected Software
Sep 8, 2021
CVE Published
via MITRE·01:45 PM
Data Sourced
via MITRE·01:45 PM
DescriptionWeakness
Feb 24, 2026
Updated
via Apple·07:00 PM
DescriptionWeaknessAffected Software
Updated
via Apple·07:00 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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Frequently Asked Questions

1

What is CVE-2021-30759?

CVE-2021-30759 is a vulnerability in the FontParser component that allowed for a stack overflow, which has been addressed with improved input validation.

2

Which software versions are affected by CVE-2021-30759?

CVE-2021-30759 affects Apple Mojave, Apple WatchOS up to version 7.6, Apple tvOS up to version 14.7, Apple Catalina, and Apple macOS Big Sur up to version 11.5.

3

How severe is the CVE-2021-30759 vulnerability?

The severity of CVE-2021-30759 is not provided in the given information.

4

How can I fix the CVE-2021-30759 vulnerability?

To fix the CVE-2021-30759 vulnerability, make sure to update your software to the latest version provided by Apple.

5

Where can I find more information about CVE-2021-30759?

More information about CVE-2021-30759 can be found on the official Apple support website at the provided references.

Company

Resources

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