CVE-2021-29974: Medium severity firefox vulnerability

Published Jul 13, 2021
·
Updated

When network partitioning was enabled, e.g. as a result of Enhanced Tracking Protection settings, a TLS error page would allow the user to override an error on a domain which had specified HTTP Strict Transport Security (which implies that the error should not be override-able.) This issue did not affect the network connections, and they were correctly upgraded to HTTPS automatically.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<90
90
Mozilla Firefox<90.0

Event History

Jul 13, 2021
CVE Published
12:00 AM
Aug 5, 2021
CVE Published
via MITRE·07:46 PM
Data Sourced
via MITRE·07:46 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-29974?

The severity of CVE-2021-29974 is considered moderate due to its implications on HTTP Strict Transport Security.

2

How do I fix CVE-2021-29974?

To fix CVE-2021-29974, users should update Firefox to version 90.0 or later.

3

Which versions of Firefox are affected by CVE-2021-29974?

CVE-2021-29974 affects all versions of Firefox prior to 90.0.

4

What issue does CVE-2021-29974 introduce regarding TLS error pages?

CVE-2021-29974 allows users to override a TLS error page on domains with HTTP Strict Transport Security enabled.

5

Is there a workaround for CVE-2021-29974 until I can update?

Currently, the only reliable workaround for CVE-2021-29974 is to disable Enhanced Tracking Protection settings.

Contact

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