CVE-2021-21176

Name: CVE-2021-21176
Creator: NVD / NIST
Published: 2021-03-09T18:15:17+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.5/10EPSS 1.70%

Last modified Jun 17, 2026

CVE-2021-21176 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Inappropriate implementation in full screen mode in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to spoof the contents of the Omnibox (URL bar) via a crafted HTML page.. EPSS estimates a 1.70% chance of exploitation in the next 30 days.

Description

Inappropriate implementation in full screen mode in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to spoof the contents of the Omnibox (URL bar) via a crafted HTML page.

Metrics

CVSS 3.1

6.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N

EPSS Probability

1.70%

74.4th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
Google	Chrome	< 89.0.4389.72
Fedoraproject	Fedora	32
Fedoraproject	Fedora	33
Fedoraproject	Fedora	34
Debian	Debian Linux	10.0

References

https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop.htmlRelease Notes, Vendor Advisory
https://crbug.com/1170584Exploit, Issue Tracking, Patch, Permissions Required, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BBT54RKAE5XLMWSHLVUKJ7T2XHHYMXLH/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FE5SIKEVYTMDCC5OSXGOM2KRPYLHYMQX/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCIDZ77XUDMB2EBPPWCQXPEIJERDNSNT/
https://security.gentoo.org/glsa/202104-08Third Party Advisory
https://www.debian.org/security/2021/dsa-4886Third Party Advisory
https://chromereleases.googleblog.com/2021/03/stable-channel-update-for-desktop.htmlRelease Notes, Vendor Advisory
https://crbug.com/1170584Exploit, Issue Tracking, Patch, Permissions Required, Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BBT54RKAE5XLMWSHLVUKJ7T2XHHYMXLH/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/FE5SIKEVYTMDCC5OSXGOM2KRPYLHYMQX/
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LCIDZ77XUDMB2EBPPWCQXPEIJERDNSNT/
https://security.gentoo.org/glsa/202104-08Third Party Advisory
https://www.debian.org/security/2021/dsa-4886Third Party Advisory

Timeline

Published: Mar 9, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-21176?

Inappropriate implementation in full screen mode in Google Chrome prior to 89.0.4389.72 allowed a remote attacker to spoof the contents of the Omnibox (URL bar) via a crafted HTML page.

How severe is CVE-2021-21176?

CVE-2021-21176 has a CVSS score of 6.5/10 (MEDIUM severity). The EPSS model estimates a 1.70% probability of exploitation in the next 30 days.

How do I fix CVE-2021-21176?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-21176?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST