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VULNERABILITIES

CVE-2021-23969 Details

Description

As specified in the W3C Content Security Policy draft, when creating a violation report, "User agents need to ensure that the source file is the URL requested by the page, pre-redirects. If that’s not possible, user agents need to strip the URL down to an origin to avoid unintentional leakage." Under certain types of redirects, Firefox incorrectly set the source file to be the destination of the redirects. This was fixed to be the redirect destination's origin. This vulnerability affects Firefox < 86, Thunderbird < 78.8, and Firefox ESR < 78.8.

Metrics

CVSS 3.x Severity and Vector Strings:

NIST: [email protected]CVSS-B:4.3 MEDIUMVector:CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

References to Advisories, Solutions, and Tools

By selecting these links, you will be leaving this site. These are references gathered from the official CVE record and are not endorsed by Volerion.

URLSource(s)Tag(s)
https://bugzilla.mozilla.org/show_bug.cgi?id=1542194 CVEIssue TrackingPermissions RequiredVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/03/msg00000.html CVEMailing ListThird Party Advisory
https://security.gentoo.org/glsa/202104-09 CVEThird Party Advisory
https://security.gentoo.org/glsa/202104-10 CVEThird Party Advisory
https://www.debian.org/security/2021/dsa-4866 CVEThird Party Advisory

see all 16 references

Weakness Enumeration

CWE-IDCWE NameSource
NVD-CWE-noinfoInsufficient Information to Classify Weakness[email protected]

Affected Products

ProductVersions
mozilla firefox
< 86.0

CPE

  • cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
mozilla firefox esr
< 78.8

CPE

  • cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
mozilla thunderbird
< 78.8

CPE

  • cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.
debian debian linux
9.0
10.0

CPE

  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

8 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2021-23969
NVD Published Date:
Feb 26, 2021
NVD Last Modified:
Jun 17, 2026
Source:
[email protected]
CVE-2021-23969 Details - Not Deferred