CVE-2021-23968

MediumCVSS 4.3/10Last modified Jun 17, 2026

Description

If Content Security Policy blocked frame navigation, the full destination of a redirect served in the frame was reported in the violation report; as opposed to the original frame URI. This could be used to leak sensitive information contained in such URIs. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

Metrics

CVSS 3.1 4.3/10CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Weakness enumeration

CWE-209

Affected software

Vendor	Product	Versions
Mozilla	Firefox	< 86
Mozilla	Thunderbird	< 78.8
Mozilla	Firefox ESR	< 78.8

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1687342Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00000.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202104-09Third Party Advisory
https://security.gentoo.org/glsa/202104-10Third Party Advisory
https://www.debian.org/security/2021/dsa-4866Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-08/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-09/Release Notes, Vendor Advisory
https://bugzilla.mozilla.org/show_bug.cgi?id=1687342Issue Tracking, Permissions Required, Vendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00000.htmlMailing List, Third Party Advisory
https://security.gentoo.org/glsa/202104-09Third Party Advisory
https://security.gentoo.org/glsa/202104-10Third Party Advisory
https://www.debian.org/security/2021/dsa-4866Third Party Advisory
https://www.mozilla.org/security/advisories/mfsa2021-07/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-08/Release Notes, Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2021-09/Release Notes, Vendor Advisory

Timeline

Published: Feb 26, 2021
Last modified: Jun 17, 2026
NVD status: Modified

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