cbcvebase.
CVE-2021-23986
published 2021-03-31

CVE-2021-23986: A malicious extension with the 'search' permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this…

PriorityP431medium6.5CVSS 3.1
AVNACLPRNUIRSUCHINAN
EPSS
0.44%
35.0th percentile
A malicious extension with the 'search' permission could have installed a new search engine whose favicon referenced a cross-origin URL. The response to this cross-origin request could have been read by the extension, allowing a same-origin policy bypass by the extension, which should not have cross-origin permissions. This cross-origin request was made without cookies, so the sensitive information disclosed by the violation was limited to local-network resources or resources that perform IP-based authentication. This vulnerability affects Firefox < 87.

Affected

7 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 87.0-1 (sid)firefox 87.0-1 (sid)
mozillafirefox< 87.087.0
mozillafirefox
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.16.04.287.0+build3-0ubuntu0.16.04.2
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.18.04.287.0+build3-0ubuntu0.18.04.2
mozillafirefox>= 0 < 87.0+build3-0ubuntu0.20.04.287.0+build3-0ubuntu0.20.04.2
mozillafirefox>= unspecified < 8787

CVSS provenance

nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
nvdv2.04.3MEDIUMAV:N/AC:M/Au:N/C:P/I:N/A:N
osv8.1HIGH
vendor_ubuntu8.1HIGH
vendor_debian6.5MEDIUM
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