CVE-2020-12391

Documents formed using data: URLs in an OBJECT element failed to inherit the CSP of the creating context. This allowed the execution of scripts that should have been blocked, albeit with a unique opaque origin. This vulnerability affects Firefox < 76.

• CWE-863

• https://bugzilla.mozilla.org/show_bug.cgi?id=1457100Permissions Required
• https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory
• https://bugzilla.mozilla.org/show_bug.cgi?id=1457100Permissions Required
• https://www.mozilla.org/security/advisories/mfsa2020-16/Vendor Advisory

Published

May 26, 2020

Last Modified

Jun 17, 2026

Status

Modified

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