Main Vulnerability Database Vulnerabilities #VU134645

Spoofing attack in Mozilla Firefox and Firefox for Android - CVE-2026-12323

Published: June 16, 2026

Vulnerability identifier: #VU134645

CSH Severity: Low

CVSS v4: 4.6 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-12323

CWE-ID: CWE-451

Exploitation vector: Remote access

Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to spoof content.

The vulnerability exists due to improper UI restriction in the DOM: Core & HTML component when rendering content. A remote attacker can present crafted content to spoof content.

Affected software

Mozilla Firefox
Firefox for Android
Mozilla Thunderbird

How to mitigate CVE-2026-12323

Install security update from vendor's website.

Mozilla Firefox - update to 152.0
Firefox for Android - update to 152.0
Mozilla Thunderbird - update to 152.0

External References

https://www.mozilla.org/en-US/security/advisories/mfsa2026-57/
https://bugzilla.mozilla.org/show_bug.cgi?id=2035027

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