CVE-2021-1821: Input Validation

Published May 24, 2021
·
Updated

A logic issue was addressed with improved state management. This issue is fixed in watchOS 7.6, macOS Big Sur 11.5. Visiting a maliciously crafted webpage may lead to a system denial of service.

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

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

— Apple

AppKit. An information disclosure issue was addressed by removing the vulnerable code.

— Apple

Credit

Georgi Valkov (httpstorm.com), Zachary Keffaber@@QuickUpdate5, Denis Tokarev@@illusionofcha0s, Csaba Fitzl@@theevilbit(Offensive Security), tr3e, JunDong Xie(Ant Security Light), 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), tr3e(Trend Micro Zero Day Initiative), hjy79425575(Trend Micro Zero Day Initiative), Jzhu(Baidu Security), Ye Zhang@@co0py_Cat(Baidu Security), Mickey Jin@@patch1t(Trend Micro working with Trend Micro Zero Day Initiative), CVE-2021-3518, Christoph Guttandin(Media Codings), Sergei Glazunov(Google Project Zero), Ivan Fratric(Google Project Zero), George Nosenko, ryuzaki, Zhongcheng Li (CK01), Ron Waisberg@@epsilan, Gary Nield(ECSC Group plc), Wojciech Reguła@@_r3ggi(SecuRing), Matt Shockley (twitter.com/mattshockl)(Offensive Security), CFF(Topsec Alpha Team), Anonymous(Trend Micro Zero Day Initiative), 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

6 affected componentsFixes available
Apple macOS Big Sur<11.5
11.5
Apple WatchOS<7.6
7.6
Apple macOS<11.5
Apple WatchOS<7.6
Apple iOS<14.6
14.6
Apple iPadOS<14.6
14.6

Event History

Jul 19, 2021
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Jul 21, 2021
Updated
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
Affected Software
Oct 28, 2021
CVE Published
via MITRE·06:16 PM
Data Sourced
via MITRE·06:16 PM
DescriptionWeakness

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-2021-1821?

CVE-2021-1821 is a vulnerability in the Networking component of Apple watchOS, macOS Big Sur, iOS, and iPadOS.

2

What is the severity of CVE-2021-1821?

The severity of CVE-2021-1821 is not mentioned in the provided information.

3

How does CVE-2021-1821 affect Apple watchOS?

CVE-2021-1821 affects Apple watchOS version up to 7.6.

4

How does CVE-2021-1821 affect macOS Big Sur?

CVE-2021-1821 affects macOS Big Sur version up to 11.5.

5

How does CVE-2021-1821 affect iOS and iPadOS?

CVE-2021-1821 affects iOS and iPadOS version up to 14.6.

6

How can I fix CVE-2021-1821?

To fix CVE-2021-1821, update Apple watchOS to version 7.6, macOS Big Sur to version 11.5, and iOS and iPadOS to version 14.6.

Company

Resources

Contact

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