vulnerability
MFSA2021-48 Firefox: Security Vulnerabilities fixed in Firefox 94 (CVE-2021-38503)
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 8 | (AV:N/AC:L/Au:N/C:P/I:P/A:P) | Nov 2, 2021 | Nov 3, 2021 | Mar 27, 2026 |
Severity
8
CVSS
(AV:N/AC:L/Au:N/C:P/I:P/A:P)
Published
Nov 2, 2021
Added
Nov 3, 2021
Modified
Mar 27, 2026
Description
The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the top-level frame. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.
Solution
mozilla-firefox-upgrade-94_0
Rapid7 Labs
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