CVE-2020-6798: XSS

Published Feb 11, 2020
·
Updated

If a <template> tag was used in a <select%gt; tag, the parser could be confused and allow JavaScript parsing and execution when it should not be allowed. A site that relied on the browser behaving correctly could suffer a cross-site scripting vulnerability as a result.

Other sources

If a template tag was used in a select tag, the parser could be confused and allow JavaScript parsing and execution when it should not be allowed. A site that relied on the browser behaving correctly could suffer a cross-site scripting vulnerability as a result. In general, this flaw cannot be exploited through email in the Thunderbird product because scripting is disabled when reading mail, but is potentially a risk in browser or browser-like contexts. This vulnerability affects Thunderbird < 68.5, Firefox < 73, and Firefox < ESR68.5.

Launchpad

Affected Software

9 affected componentsFixes available
Mozilla Thunderbird<68.5
68.5
Mozilla Firefox<73.0
Mozilla Firefox ESR<68.5.0
Mozilla Thunderbird<68.5.0
Mozilla Firefox ESR<68.5
68.5
Mozilla Firefox<73
73
debian/firefox
152.0.6-1
debian/firefox-esr
115.14.0esr-1~deb11u1140.12.0esr-1~deb11u1140.12.0esr-1~deb12u1140.12.0esr-1~deb13u1140.12.0esr-1
debian/thunderbird
1:115.12.0-1~deb11u11:140.12.0esr-1~deb11u11:140.12.0esr-1~deb12u11:140.12.0esr-1~deb13u11:140.12.0esr-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Thunderbird to a version that resolves this vulnerability.

    Fixed in 68.5
  2. Upgrade

    Upgrade Firefox ESR to a version that resolves this vulnerability.

    Fixed in 68.5
  3. Upgrade

    Upgrade Firefox to a version that resolves this vulnerability.

    Fixed in 73
  4. Upgrade

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

    Fixed in 152.0.6-1
  5. Upgrade

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

    Fixed in 115.14.0esr-1~deb11u1Fixed in 140.12.0esr-1~deb11u1Fixed in 140.12.0esr-1~deb12u1Fixed in 140.12.0esr-1~deb13u1Fixed in 140.12.0esr-1
  6. Upgrade

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

    Fixed in 1:115.12.0-1~deb11u1Fixed in 1:140.12.0esr-1~deb11u1Fixed in 1:140.12.0esr-1~deb12u1Fixed in 1:140.12.0esr-1~deb13u1Fixed in 1:140.12.0esr-1
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 68.5
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 73

Event History

Feb 11, 2020
CVE Published
via Mozilla·12:00 AM
Mar 2, 2020
CVE Published
via MITRE·04:05 AM
Data Sourced
via MITRE·04:05 AM
DescriptionWeakness
Data Sourced
via NVD·05:15 AM
DescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:51 PM
Description
Jul 7, 2026
Data Sourced
via Ubuntu·03:56 AM
RemedyDescriptionSeverityAffected Software
Jul 16, 2026
Data Sourced
via Debian·11:42 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is CVE-2020-6798?

CVE-2020-6798 is a vulnerability that allows JavaScript parsing and execution in a select tag when a template tag is used, resulting in a potential cross-site scripting vulnerability.

2

Which software is affected by CVE-2020-6798?

Mozilla Firefox ESR version 68.5, Mozilla Firefox up to version 73.0, Mozilla Thunderbird up to version 68.5, and certain versions of Ubuntu Firefox and Thunderbird packages are affected by CVE-2020-6798.

3

What is the severity of CVE-2020-6798?

The severity of CVE-2020-6798 is medium with a CVSS score of 6.1.

4

How can I fix CVE-2020-6798?

Update your Mozilla Firefox or Thunderbird to the latest version, or apply the recommended updates for the affected Ubuntu packages.

5

Where can I find more information about CVE-2020-6798?

You can find more information about CVE-2020-6798 on the Mozilla Bugzilla and Mozilla Security Advisories websites.

Contact

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