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.
[
{
"product": "Firefox",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "94",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
},
{
"product": "Thunderbird",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "91.3",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
},
{
"product": "Firefox ESR",
"vendor": "Mozilla",
"versions": [
{
"lessThan": "91.3",
"status": "affected",
"version": "unspecified",
"versionType": "custom"
}
]
}
]
bugzilla.mozilla.org/show_bug.cgi?id=1730750
lists.debian.org/debian-lts-announce/2021/12/msg00030.html
lists.debian.org/debian-lts-announce/2022/01/msg00001.html
security.gentoo.org/glsa/202202-03
security.gentoo.org/glsa/202208-14
www.debian.org/security/2021/dsa-5026
www.debian.org/security/2022/dsa-5034
www.mozilla.org/security/advisories/mfsa2021-48/
www.mozilla.org/security/advisories/mfsa2021-49/
www.mozilla.org/security/advisories/mfsa2021-50/