CVE-2021-38505: Medium severity thunderbird vulnerability

Published Nov 2, 2021
·
Updated

Microsoft introduced a new feature in Windows 10 known as Cloud Clipboard which, if enabled, will record data copied to the clipboard to the cloud, and make it available on other computers in certain scenarios. Applications that wish to prevent copied data from being recorded in Cloud History must use specific clipboard formats; and Firefox before versions 94 and ESR 91.3 did not implement them. This could have caused sensitive data to be recorded to a user's Microsoft account.This bug only affects Firefox for Windows 10+ with Cloud Clipboard enabled. Other operating systems are unaffected.

Other sources

Microsoft introduced a new feature in Windows 10 known as Cloud Clipboard which, if enabled, will record data copied to the clipboard to the cloud, and make it available on other computers in certain scenarios. Applications that wish to prevent copied data from being recorded in Cloud History must use specific clipboard formats; and Thunderbird before version 91.3 did not implement them. This could have caused sensitive data to be recorded to a user's Microsoft account.This bug only affects Thunderbird for Windows 10+ with Cloud Clipboard enabled. Other operating systems are unaffected.

Mozilla

Microsoft introduced a new feature in Windows 10 known as Cloud Clipboard which, if enabled, will record data copied to the clipboard to the cloud, and make it available on other computers in certain scenarios. Applications that wish to prevent copied data from being recorded in Cloud History must use specific clipboard formats; and Firefox before versions 94 and ESR 91.3 did not implement them. This could have caused sensitive data to be recorded to a user's Microsoft account. This bug only affects Firefox for Windows 10+ with Cloud Clipboard enabled. Other operating systems are unaffected.. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Affected Software

7 affected componentsFixes available
Mozilla Thunderbird<91.3
91.3
Mozilla Firefox<94
94
Mozilla Firefox ESR<91.3
91.3
Mozilla Firefox<94.0
Mozilla Firefox ESR<91.3.0
Mozilla Thunderbird<91.3.0
Microsoft Windows 10

Event History

Nov 2, 2021
CVE Published
12:00 AM
Dec 8, 2021
CVE Published
via MITRE·09:21 PM
Data Sourced
via MITRE·09:21 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-38505?

CVE-2021-38505 is a vulnerability in Microsoft Windows 10, where the Cloud Clipboard feature records data copied to the clipboard to the cloud.

2

How does CVE-2021-38505 affect Mozilla Thunderbird?

CVE-2021-38505 affects Mozilla Thunderbird versions up to and excluding 91.3.0

3

How does CVE-2021-38505 affect Mozilla Firefox?

CVE-2021-38505 affects Mozilla Firefox versions up to and excluding 94.0

4

Is Microsoft Windows 10 affected by CVE-2021-38505?

No, Microsoft Windows 10 is not vulnerable to CVE-2021-38505

5

What is the severity of CVE-2021-38505?

CVE-2021-38505 has a severity value of 6.5 (High)

Contact

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