Cross-site Scripting (XSS) The advisory has been revoked - it doesn't affect any version of package thunderbird  (opens in a new tab)


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EPSS
0.3% (54th percentile)

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  • Snyk IDSNYK-UBUNTU2004-THUNDERBIRD-1041288
  • published18 Nov 2020
  • disclosed9 Dec 2020

Introduced: 18 Nov 2020

CVE-2020-26958  (opens in a new tab)
CWE-79  (opens in a new tab)

Amendment

The Ubuntu security team deemed this advisory irrelevant for Ubuntu:20.04.

NVD Description

Note: Versions mentioned in the description apply only to the upstream thunderbird package and not the thunderbird package as distributed by Ubuntu.

Firefox did not block execution of scripts with incorrect MIME types when the response was intercepted and cached through a ServiceWorker. This could lead to a cross-site script inclusion vulnerability, or a Content Security Policy bypass. This vulnerability affects Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5.