PatchSiren

PatchSiren cyber security CVE debrief

CVE-2026-12323 Mozilla CVE debrief

CVE-2026-12323 is a spoofing issue in the DOM: Core & HTML component. The vulnerability was fixed in Firefox 152. The CVE was published and modified on June 16, 2026, at 13:16:33 UTC. The vendor is currently listed as Unknown Vendor, but evidence suggests the vulnerability may be related to Mozilla. For more information, see [cve-org](https://www.cve.org/CVERecord?id=CVE-2026-12323) and [nvd](https://nvd.nist.gov/vuln/detail/CVE-2026-12323).

Vendor
Mozilla
Product
Firefox
CVSS
MEDIUM 5.4
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-16
Original CVE updated
2026-06-16
Advisory published
2026-06-16
Advisory updated
2026-06-16

Who should care

Users of Firefox browser, particularly those using versions prior to Firefox 152, should be aware of this vulnerability and take steps to update their browser.

Technical summary

A spoofing issue was found in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 152.

Defensive priority

Medium

Recommended defensive actions

  • Update Firefox to version 152 or later.

Evidence notes

The vendor is currently listed as Unknown Vendor, but evidence suggests the vulnerability may be related to Mozilla.

Official resources

CVE-2026-12323 was published and modified on June 16, 2026, at 13:16:33 UTC.