CVE-2021-30817: Race Condition

Published Jul 21, 2021
·
Updated

A permissions issue was addressed with improved validation. This issue is fixed in macOS Big Sur 11.5. A malicious application may be able to access data about the accounts the user is using Family Sharing with.

Other sources

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

Audio. This issue was addressed with improved checks.

— Apple

Credit

Csaba Fitzl@@theevilbit(Offensive Security), Denis Tokarev@@illusionofcha0s, hjy79425575(Trend Micro Zero Day Initiative), tr3e, George Nosenko, JunDong Xie(Ant Security Light), ryuzaki, Zhongcheng Li (CK01), Ron Waisberg@@epsilan, Tim Michaud@@TimGMichaud(Zoom Video Communications), Gary Nield(ECSC Group plc), Mickey Jin@@patch1t(Trend Micro), Sunglin(Knownsec 404 team), Yizhuo Wang(Group of Software Security In Progress), Linus Henze (pinauten.de), Wojciech Reguła@@_r3ggi(SecuRing), tr3e(Trend Micro Zero Day Initiative), Matt Shockley (twitter.com/mattshockl)(Offensive Security), Jzhu(Baidu Security), Ye Zhang@@co0py_Cat(Baidu 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), CVE-2021-3518, Georgi Valkov (httpstorm.com), Mickey Jin@@patch1t(Trend Micro working with Trend Micro Zero Day Initiative), Christoph Guttandin(Media Codings), Sergei Glazunov(Google Project Zero), Ivan Fratric(Google Project Zero), ABC Research s.r.o

Affected Software

2 affected componentsFixes available
Apple macOS Big Sur<11.5
11.5
macOS<11.5

Event History

Jul 21, 2021
Data Sourced
via Apple·12:00 AM
DescriptionWeaknessAffected Software
Updated
via Apple·12:00 AM
DescriptionWeakness
Oct 28, 2021
CVE Published
via MITRE·06:17 PM
Data Sourced
via MITRE·06:17 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2021-30817.

2

What is the title of this vulnerability?

The title of this vulnerability is 'Family Sharing. A permissions issue was addressed with improved validation.'

3

What is the affected software?

The affected software is macOS Big Sur version 11.5.

4

How can I fix this vulnerability?

Apple has addressed this vulnerability with improved validation. It is recommended to update to macOS Big Sur version 11.5.

5

Where can I find more information about this vulnerability?

You can find more information about this vulnerability on the [Apple Support website](https://support.apple.com/en-us/HT212602).

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203