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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.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-12323 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-12323

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-12323 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-12323

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.