vulnerability
MFSA2020-51 Firefox: Security Vulnerabilities fixed in Firefox ESR 78.5 (CVE-2020-26958)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Nov 17, 2020 | Nov 18, 2020 | Feb 10, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Nov 17, 2020
Added
Nov 18, 2020
Modified
Feb 10, 2026
Description
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.
Solution
mozilla-firefox-esr-upgrade-78_5
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