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VULNERABILITIES

CVE-2021-38506 Details

Description

Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning to the user. This could lead to spoofing attacks on the browser UI including phishing. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

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:N/I:L/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=1730750 CVEIssue TrackingPermissions RequiredVendor Advisory
https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html CVEMailing ListThird Party Advisory
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html CVEMailing ListThird Party Advisory
https://security.gentoo.org/glsa/202202-03 CVEThird Party Advisory
https://security.gentoo.org/glsa/202208-14 CVEThird Party Advisory

see all 20 references

Weakness Enumeration

CWE-IDCWE NameSource
CWE-1021Improper Restriction of Rendered UI Layers or Frames[email protected]

Affected Products

ProductVersions
mozilla firefox
< 94.0

CPE

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

Remediation

  • No remediation found in references.
mozilla firefox esr
< 91.3.0

CPE

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

Remediation

  • No remediation found in references.
mozilla thunderbird
< 91.3.0

CPE

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

Remediation

  • No remediation found in references.
debian debian linux
9.0
10.0
11.0

CPE

  • cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
  • cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
  • cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

Remediation

  • No remediation found in references.

Change History

13 change records found show changes

QUICK INFO

CVE Dictionary Entry:
CVE-2021-38506
NVD Published Date:
Dec 8, 2021
NVD Last Modified:
Jun 17, 2026
Source:
[email protected]
CVE-2021-38506 Details - Not Deferred