cbcvebase.
CVE-2021-23969
published 2021-02-26

CVE-2021-23969: 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…

PriorityP418medium4.3CVSS 3.1
AVNACLPRNUIRSUCLINAN
EPSS
1.21%
64.8th percentile
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.

Affected

15 ranges
VendorProductVersion rangeFixed in
debiandebian_linux
debiandebian_linux
debianfirefox< firefox 86.0-1 (sid)firefox 86.0-1 (sid)
debianfirefox-esr< firefox 86.0-1 (sid)firefox 86.0-1 (sid)
debianthunderbird< firefox 86.0-1 (sid)firefox 86.0-1 (sid)
mozillafirefox< 8686
mozillafirefox< 86.086.0
mozillafirefox
mozillafirefox_esr< 78.878.8
mozillathunderbird< 78.878.8
mozillathunderbird>= 0 < 1:78.8.0-11:78.8.0-1
mozillathunderbird>= 0 < 1:78.8.0-11:78.8.0-1
mozillathunderbird>= 0 < 1:78.8.0-11:78.8.0-1
mozillathunderbird>= 0 < 1:78.8.0-11:78.8.0-1
mozillathunderbird>= 0 < 1:78.8.1+build1-0ubuntu0.20.04.11:78.8.1+build1-0ubuntu0.20.04.1

CVSS provenance

nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:P/I:N/A:N
osv4.3MEDIUM
vendor_debian4.3MEDIUM
vendor_redhat4.3MEDIUM
vendor_ubuntu4.3MEDIUM
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