CVE-2020-26966: Medium severity thunderbird vulnerability

Published Nov 17, 2020
·
Updated

Searching for a single word from the address bar caused an mDNS request to be sent on the local network searching for a hostname consisting of that string; resulting in an information leak. Note: This issue only affected Windows operating systems. Other operating systems are unaffected.. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.

Other sources

Searching for a single word from the address bar caused an mDNS request to be sent on the local network searching for a hostname consisting of that string; resulting in an information leak.Note: This issue only affected Windows operating systems. Other operating systems are unaffected.

Affected Software

7 affected componentsFixes available
Mozilla Thunderbird<78.5
78.5
Mozilla Firefox<83
83
Mozilla Firefox ESR<78.5
78.5
Mozilla Firefox<83.0
Mozilla Firefox ESR<78.5
Mozilla Thunderbird<78.5
Microsoft Windows

Event History

Nov 17, 2020
CVE Published
12:00 AM
Dec 9, 2020
CVE Published
via MITRE·12:25 AM
Data Sourced
via MITRE·12:25 AM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2020-26966?

CVE-2020-26966 is a vulnerability that affects Windows operating systems and allows for an information leak when searching for a single word from the address bar in Mozilla Firefox and Thunderbird.

2

Which operating systems are affected by CVE-2020-26966?

Only Windows operating systems are affected by CVE-2020-26966.

3

Which software versions are affected by CVE-2020-26966?

Mozilla Firefox ESR versions up to 78.5, Mozilla Thunderbird up to 78.5, and Mozilla Firefox up to version 83.0 are affected by CVE-2020-26966.

4

What is the severity of CVE-2020-26966?

CVE-2020-26966 has a severity rating of 6.5 (Medium).

5

How can I fix CVE-2020-26966?

To mitigate the vulnerability, update Mozilla Firefox ESR to version 78.5, Mozilla Thunderbird to version 78.5, and Mozilla Firefox to version 83.0 or later.

Contact

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