cbcvebase.
CVE-2021-38503
published 2021-12-08

CVE-2021-38503: The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the…

PriorityP355critical10CVSS 3.1
AVNACLPRNUINSCCHIHAH
EPSS
3.83%
88.8th percentile
The iframe sandbox rules were not correctly applied to XSLT stylesheets, allowing an iframe to bypass restrictions such as executing scripts or navigating the top-level frame. This vulnerability affects Firefox < 94, Thunderbird < 91.3, and Firefox ESR < 91.3.

Affected

21 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debiandebian_linux
debianfirefox< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
debianfirefox-esr< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
debianthunderbird< firefox 94.0-1 (sid)firefox 94.0-1 (sid)
mozillafirefox< 94.094.0
mozillafirefox
mozillafirefox>= 0 < 94.0+build3-0ubuntu0.18.04.194.0+build3-0ubuntu0.18.04.1
mozillafirefox>= 0 < 94.0+build3-0ubuntu0.20.04.194.0+build3-0ubuntu0.20.04.1
mozillafirefox>= unspecified < 9494
mozillafirefox_esr< 91.391.3
mozillafirefox_esr>= unspecified < 91.391.3
mozillathunderbird< 91.391.3
mozillathunderbird>= 0 < 1:91.4.1-1~deb11u11:91.4.1-1~deb11u1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.3.0-11:91.3.0-1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.18.04.11:91.5.0+build1-0ubuntu0.18.04.1
mozillathunderbird>= 0 < 1:91.5.0+build1-0ubuntu0.20.04.11:91.5.0+build1-0ubuntu0.20.04.1
mozillathunderbird>= unspecified < 91.391.3

CVSS provenance

nvdv3.110.0CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
osv10.0CRITICAL
vendor_debian10.0CRITICAL
vendor_redhat10.0CRITICAL
vendor_ubuntu10.0CRITICAL
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