CVE-2021-43533: Medium severity firefox vulnerability

Published Nov 2, 2021
·
Updated

When parsing internationalized domain names, high bits of the characters in the URLs were sometimes stripped, resulting in inconsistencies that could lead to user confusion or attacks such as phishing.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<94
94
Mozilla Firefox<94.0

Event History

Nov 2, 2021
CVE Published
12:00 AM
Dec 8, 2021
CVE Published
via MITRE·09:20 PM
Data Sourced
via MITRE·09:20 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is CVE-2021-43533?

CVE-2021-43533 is a vulnerability that affects Firefox versions before 94.

2

How does CVE-2021-43533 affect Firefox?

CVE-2021-43533 affects Firefox versions before 94 by causing inconsistencies in the parsing of internationalized domain names, which can lead to user confusion or phishing attacks.

3

What is the severity of CVE-2021-43533?

The severity of CVE-2021-43533 is medium with a CVSS score of 4.3.

4

How can I fix CVE-2021-43533?

To fix CVE-2021-43533, update your Firefox browser to version 94 or above.

5

Where can I find more information about CVE-2021-43533?

For more information about CVE-2021-43533, you can refer to the following sources: [Mozilla Bugzilla](https://bugzilla.mozilla.org/show_bug.cgi?id=1724233), [Mozilla Security Advisories](https://www.mozilla.org/en-US/security/advisories/mfsa2021-48/)

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