CVE-2021-21139

Public Exploit

Description

Inappropriate implementation in iframe sandbox in Google Chrome prior to 88.0.4324.96 allowed a remote attacker to bypass navigation restrictions via a crafted HTML page.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.83% Top 30%
Vendor Advisory googleblog.com Vendor Advisory crbug.com
Affected: Google Chrome
Published at:
Updated at:

References

Link Tags
https://chromereleases.googleblog.com/2021/01/stable-channel-update-for-desktop_19.html release notes vendor advisory
https://crbug.com/937131 issue tracking patch vendor advisory exploit
https://msrc.microsoft.com/update-guide/en-US/vulnerability/CVE-2021-21139 third party advisory

Frequently Asked Questions

What is the severity of CVE-2021-21139?
CVE-2021-21139 has been scored as a medium severity vulnerability.
How to fix CVE-2021-21139?
To fix CVE-2021-21139, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-21139 being actively exploited in the wild?
It is possible that CVE-2021-21139 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-21139?
CVE-2021-21139 affects Google Chrome.
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