CVE-2017-7783: Input Validation

Published Aug 8, 2017
·
Updated

If a long user name is used in a username/password combination in a site URL (such as http://UserName:Password@example.com), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service.

Other sources

If a long user name is used in a username/password combination in a site URL (such as " http://UserName:Password@example.com"), the resulting modal prompt will hang in a non-responsive state or crash, causing a denial of service. This vulnerability affects Firefox < 55.

Affected Software

2 affected componentsFixes available
Mozilla Firefox<55
55
Mozilla Firefox<55.0

Event History

Aug 8, 2017
CVE Published
12:00 AM
Jun 11, 2018
CVE Published
via MITRE·09:00 PM
Data Sourced
via MITRE·09:00 PM
DescriptionWeakness

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2017-7783?

CVE-2017-7783 is classified as a denial of service vulnerability that can cause the Firefox browser to hang or crash.

2

How do I fix CVE-2017-7783?

To fix CVE-2017-7783, update Firefox to version 55.0 or later.

3

Which versions of Firefox are affected by CVE-2017-7783?

CVE-2017-7783 affects Firefox versions prior to 55.0.

4

What type of attack does CVE-2017-7783 enable?

CVE-2017-7783 enables denial of service attacks through the use of excessively long usernames in URL-encoded authentication.

5

Is there a workaround for CVE-2017-7783?

There is no official workaround for CVE-2017-7783, but avoiding long usernames in URL-encoded authentication can help mitigate the issue.

Contact

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