CVE-2020-26976: Medium severity thunderbird vulnerability

Published Dec 15, 2020
·
Updated

When a HTTPS page was embedded in a HTTP page, and there was a service worker registered for the former, the service worker could have intercepted the request for the secure page despite the iframe not being a secure context due to the (insecure) framing.

Other sources

When a HTTPS pages was embedded in a HTTP page, and there was a service worker registered for the former, the service worker could have intercepted the request for the secure page despite the iframe not being a secure context due to the (insecure) framing.

Mozilla

Affected Software

9 affected componentsFixes available
debian/firefox
118.0.2-1
debian/firefox-esr
91.12.0esr-1~deb10u1115.3.1esr-1~deb10u1102.15.0esr-1~deb11u1115.3.1esr-1~deb11u1102.15.1esr-1~deb12u1115.3.0esr-1~deb12u1115.3.0esr-1
debian/thunderbird
1:91.12.0-1~deb10u11:115.3.1-1~deb10u11:102.13.1-1~deb11u11:115.3.1-1~deb11u11:102.15.1-1~deb12u11:115.3.1-1~deb12u11:115.3.1-1
Mozilla Thunderbird<78.7
78.7
Mozilla Firefox<84
84
Mozilla Firefox ESR<78.7
78.7
Mozilla Firefox<84.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0

Event History

Dec 15, 2020
CVE Published
via Mozilla·12:00 AM
Jan 7, 2021
CVE Published
via MITRE·01:52 PM
Data Sourced
via MITRE·01:52 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-2020-26976?

CVE-2020-26976 is considered a moderate severity vulnerability.

2

How do I fix CVE-2020-26976?

To fix CVE-2020-26976, you should update your software to the latest version as specified in the vulnerability details.

3

Which versions are affected by CVE-2020-26976?

CVE-2020-26976 affects Mozilla Firefox versions prior to 84, as well as Thunderbird and Firefox ESR versions before 78.7.

4

What kind of vulnerability is CVE-2020-26976?

CVE-2020-26976 is a security vulnerability that relates to the improper handling of HTTPS pages embedded in HTTP contexts.

5

Is CVE-2020-26976 exploitable?

Yes, CVE-2020-26976 can potentially be exploited by attackers to intercept secure communications when HTTPS content is improperly framed.

Contact

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