CVE-2020-6813

MediumCVSS 5.3/10Last modified Jun 17, 2026

Description

When protecting CSS blocks with the nonce feature of Content Security Policy, the @import statement in the CSS block could allow an attacker to inject arbitrary styles, bypassing the intent of the Content Security Policy. This vulnerability affects Firefox < 74.

Metrics

CVSS 3.1 5.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected software

Vendor	Product	Versions
Mozilla	Firefox	>= unspecified, < 74

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1605814Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-08/Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1605814Permissions Required, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2020-08/Vendor Advisory

Timeline

Published: Mar 25, 2020
Last modified: Jun 17, 2026
NVD status: Modified

Related CVEs from 2020

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