Medium severity · published Feb 9, 2021
CVE-2021-21126
Insufficient policy enforcement in extensions in Google Chrome prior to 88.0.4324.96 allowed a remote attacker to bypass site isolation via a crafted Chrome Extension
6.5
CVSS
8.7%
EPSS
No
On KEV
Description
Insufficient policy enforcement in extensions in Google Chrome prior to 88.0.4324.96 allowed a remote attacker to bypass site isolation via a crafted Chrome Extension.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)8.7% · higher than 95% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CH
Chrome · Google
before 88.0.4324.96 · source: NVD
EC
Edge Chromium · Microsoft
before 88.0.705.50 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21126
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21126
Release Notes
https://chromereleases.googleblog.com/2021/01/stable-channel-update-for-desktop_19.html
Permissions Required
https://crbug.com/1108126
Third Party Advisory
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-21126
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