Spoofing attack in Google Chromium - CVE-2026-84356

Vulnerability identifier: #VU146711

CSH Severity: Low

CVSS v4: 5.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-84356

CWE-ID: CWE-451

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to spoof the user interface.

The vulnerability exists due to UI misrepresentation in FullScreen when rendering fullscreen content. A remote attacker can present crafted fullscreen content to spoof the user interface.

User interaction is required.

Google Chromium
Google Chrome
Debian Linux
Fedora
chromium
chromium (Debian package)

Install security update from vendor's website.

Google Chromium - update to 152.0.7977.75
Google Chrome - update to 152.0.7977.75
chromium - addressed in versions 152.0.7977.75-1.el9, 152.0.7977.75-1.el10_2, 152.0.7977.75-1.el10_3, 152.0.7977.75-1.el10_4, 152.0.7977.75-1.fc43, 152.0.7977.75-1.fc44, 152.0.7977.75-1.fc45
chromium (Debian package) - update to 152.0.7977.75-1~deb13u1

• https://chromereleases.googleblog.com/2026/09/stable-channel-update-for-desktop.html
• https://crbug.com/503787232

• Multiple vulnerabilities in Google Chrome
• Debian update for chromium
• Fedora 45 update for chromium
• Fedora EPEL 10.4 update for chromium
• Fedora EPEL 9 update for chromium
• Fedora 43 update for chromium
• Fedora 44 update for chromium
• Fedora EPEL 10.2 update for chromium
• Fedora EPEL 10.3 update for chromium