CVE-2021-4321

Severity: medium (CVSS 4.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2023-07-29 · updated 2026-06-17

Description

Policy bypass in Blink in Google Chrome prior to 91.0.4472.77 allowed a remote attacker to bypass content security policy via a crafted HTML page. (Chromium security severity: Low)

Affected products

Google Chrome: before 91.0.4472.77 — fixed in 91.0.4472.77

How to fix

Upgrade to a fixed version: Google Chrome 91.0.4472.77. Check the vendor advisory for mitigations.

References

https://chromereleases.googleblog.com/2021/05/stable-channel-update-for-desktop_25.html
https://crbug.com/1161891
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PQKT7EGDD2P3L7S3NXEDDRCPK4NNZNWJ/
https://chromereleases.googleblog.com/2021/05/stable-channel-update-for-desktop_25.html
https://crbug.com/1161891
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PQKT7EGDD2P3L7S3NXEDDRCPK4NNZNWJ/

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