Medium severity · published Dec 8, 2021
CVE-2021-38506
Through a series of navigations, Firefox could have entered fullscreen mode without notification or warning to the user
4.3
CVSS
1.5%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.5% · higher than 74% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FI
Firefox · Mozilla
before 94.0 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0; 11.0 · source: NVD
FE
Firefox Esr · Mozilla
before 91.3.0 · source: NVD
TH
Thunderbird · Mozilla
before 91.3.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-38506
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-38506
Issue Tracking
https://bugzilla.mozilla.org/show_bug.cgi?id=1730750
Mailing List
https://lists.debian.org/debian-lts-announce/2021/12/msg00030.html
Mailing List
https://lists.debian.org/debian-lts-announce/2022/01/msg00001.html
Third Party Advisory
https://security.gentoo.org/glsa/202202-03
Third Party Advisory
https://security.gentoo.org/glsa/202208-14
Third Party Advisory
https://www.debian.org/security/2021/dsa-5026
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