CVE-2020-26976: Medium severity Mozilla 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

45 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
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox<84.0.1-r0
84.0.1-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/firefox-esr<78.7.0-r0
78.7.0-r0
alpine/librewolf<84.0.1-r0
84.0.1-r0
alpine/librewolf<84.0.1-r0
84.0.1-r0
alpine/librewolf<84.0.1-r0
84.0.1-r0
alpine/librewolf<84.0.1-r0
84.0.1-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0
alpine/thunderbird<78.7.0-r0
78.7.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade debian/firefox to a version that resolves this vulnerability.

    Fixed in 118.0.2-1
  2. Upgrade

    Upgrade debian/firefox-esr to a version that resolves this vulnerability.

    Fixed in 91.12.0esr-1~deb10u1Fixed in 115.3.1esr-1~deb10u1Fixed in 102.15.0esr-1~deb11u1Fixed in 115.3.1esr-1~deb11u1Fixed in 102.15.1esr-1~deb12u1Fixed in 115.3.0esr-1~deb12u1Fixed in 115.3.0esr-1
  3. Upgrade

    Upgrade debian/thunderbird to a version that resolves this vulnerability.

    Fixed in 1:91.12.0-1~deb10u1Fixed in 1:115.3.1-1~deb10u1Fixed in 1:102.13.1-1~deb11u1Fixed in 1:115.3.1-1~deb11u1Fixed in 1:102.15.1-1~deb12u1Fixed in 1:115.3.1-1~deb12u1Fixed in 1:115.3.1-1
  4. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 78.7
  5. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 84
  6. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 78.7
  7. Upgrade

    Upgrade alpine/firefox to a version that resolves this vulnerability.

    Fixed in 84.0.1-r0
  8. Upgrade

    Upgrade alpine/firefox-esr to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0
  9. Upgrade

    Upgrade alpine/librewolf to a version that resolves this vulnerability.

    Fixed in 84.0.1-r0
  10. Upgrade

    Upgrade alpine/thunderbird to a version that resolves this vulnerability.

    Fixed in 78.7.0-r0

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
Data Sourced
via NVD·02:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

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.

Company

Resources

Contact

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