CVE-2021-21186 Security feature bypass in Chrome

What is CVE-2021-21186?

CVE-2021-21186 is a medium-severity vulnerability in Debian Debian Linux, published on 9 Mar 2021. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official description

Insufficient policy enforcement in QR scanning in Google Chrome on iOS prior to 89.0.4389.72 allowed an attacker who convinced the user to scan a QR code to bypass navigation restrictions via a crafted QR code.

Weakness: CWE-863

Which versions are affected by CVE-2021-21186?

It affects 3 products.

Products include Debian Debian Linux, Fedoraproject Fedora, Google Chrome.

How do I fix CVE-2021-21186?

Upgrade to a fixed version.

Is CVE-2021-21186 being exploited?

There is no known exploitation of CVE-2021-21186 in the wild and no public exploit code.

Other vulnerabilities in Debian Debian Linux

• CVE-2015-3306 ProFTPD Improper Access Control Exploited Critical 10.0
• CVE-2025-49113 RoundCube Webmail Deserialization of Untrusted Data Exploited Critical 9.9
• CVE-2026-24061 GNU InetUtils Argument Injection Exploited Critical 9.8
• CVE-2025-39682 Linux Kernel Improper Check for Unusual or Exceptional Conditions Exploited Critical 9.8
• CVE-2024-9680 Mozilla Firefox Use-After-Free Exploited Critical 9.8

All Debian Debian Linux vulnerabilities

Sources

• CVE record
• NVD
• OSV
• GitHub advisory
• How this page is made

Also known as DEBIAN-CVE-2021-21186, GHSA-q9x2-h7vp-cfx6, UBUNTU-CVE-2021-21186.