vulnerability
MFSA2021-04 Firefox: Security Vulnerabilities fixed in Firefox ESR 78.7 (CVE-2020-26976)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 4 | (AV:N/AC:M/Au:N/C:N/I:P/A:N) | Jan 7, 2021 | Jan 27, 2021 | Mar 27, 2026 |
Severity
4
CVSS
(AV:N/AC:M/Au:N/C:N/I:P/A:N)
Published
Jan 7, 2021
Added
Jan 27, 2021
Modified
Mar 27, 2026
Description
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. This vulnerability affects Firefox < 84.
Solution
mozilla-firefox-esr-upgrade-78_7
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