CVE-2020-15655: Medium severity Mozilla Firefox vulnerability

Published Jul 28, 2020
·
Updated

A redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information. This vulnerability affects Firefox ESR < 78.1, Firefox < 79, and Thunderbird < 78.1.

Other sources

Mozilla Developer Rob Wu discovered that a redirected HTTP request which is observed or modified through a web extension could bypass existing CORS checks, leading to potential disclosure of cross-origin information.

Mozilla

Affected Software

12 affected componentsFixes available
Mozilla Firefox<79.0
Mozilla Firefox ESR<78.1
Mozilla Thunderbird<78.1
openSUSE Leap=15.2
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=20.04
Mozilla Thunderbird<78.1
78.1
Mozilla Firefox<79
79
Mozilla Firefox ESR<78.1
78.1
debian/firefox
148.0.2-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.8.0esr-1~deb11u11:140.6.0esr-1~deb12u11:140.8.0esr-1~deb12u11:140.6.0esr-1~deb13u11:140.8.0esr-1~deb13u11:140.8.0esr-1

Event History

Jul 28, 2020
CVE Published
via Mozilla·12:00 AM
Aug 10, 2020
CVE Published
via MITRE·05:43 PM
Data Sourced
via MITRE·05:43 PM
DescriptionWeakness
Data Sourced
via NVD·06:15 PM
DescriptionSeverityAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:43 PM
Description
Feb 23, 2026
Data Sourced
via Ubuntu·07:56 PM
RemedyDescriptionSeverityAffected Software
Mar 11, 2026
Data Sourced
via Debian·08:11 PM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the vulnerability ID for this vulnerability?

The vulnerability ID for this vulnerability is CVE-2020-15655.

2

Who discovered this vulnerability?

Mozilla Developer Rob Wu discovered this vulnerability.

3

What is the impact of this vulnerability?

This vulnerability could bypass existing CORS checks, leading to potential disclosure of cross-origin information.

4

Which software products are affected by this vulnerability?

Firefox ESR 78.1, Thunderbird 78.1, and Firefox 79 are affected by this vulnerability.

5

What is the severity of CVE-2020-15655?

The severity of CVE-2020-15655 is high (7.0).

6

How can I fix this vulnerability?

Update Firefox ESR to version 78.1, Thunderbird to version 78.1, or Firefox to version 79 to fix this vulnerability.

Contact

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