CVE-2020-12391

Description

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.69% Top 30%
Vendor Advisory mozilla.org
Affected: Mozilla Firefox
Published at:
Updated at:

References

Link Tags
https://www.mozilla.org/security/advisories/mfsa2020-16/ vendor advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1457100 permissions required

Frequently Asked Questions

What is the severity of CVE-2020-12391?
CVE-2020-12391 has been scored as a high severity vulnerability.
How to fix CVE-2020-12391?
To fix CVE-2020-12391, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2020-12391 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2020-12391 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2020-12391?
CVE-2020-12391 affects Mozilla Firefox.
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