PatchSiren cyber security CVE debrief

CVE-2026-12315 Mozilla CVE debrief

CVE-2026-12315 is a mitigation bypass vulnerability in the DOM: Security component. The vulnerability was published on [cvePublishedAt] and has not been modified since. The vendor for this vulnerability is likely Mozilla, based on evidence from the source item. The vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.

Vendor: Mozilla
Product: Firefox
CVSS: CRITICAL 9.1
CISA KEV: Not listed in stored evidence
Original CVE published: 2026-06-16
Original CVE updated: 2026-06-17
Advisory published: 2026-06-16
Advisory updated: 2026-06-17

Who should care

Users of Firefox and Firefox ESR should apply the patches to prevent exploitation of this vulnerability.

Technical summary

A mitigation bypass vulnerability exists in the DOM: Security component. This vulnerability was fixed in Firefox 152 and Firefox ESR 140.12.

Defensive priority

high

Recommended defensive actions

Apply the patches for Firefox 152 and Firefox ESR 140.12.

Evidence notes

The vendor for this vulnerability is likely Mozilla, based on evidence from the source item.

Sources and references

Verified primary and authoritative sources

CVE-2026-12315 CVE Program record
Publisher, destination, and source semantics verified

URL: https://www.cve.org/CVERecord?id=CVE-2026-12315

CVE Program - Official CVE Program record with source-provided CVE metadata.
CVE-2026-12315 NVD vulnerability detail
Publisher, destination, and source semantics verified

URL: https://nvd.nist.gov/vuln/detail/CVE-2026-12315

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

Supplemental references

Source reference
Unverified legacy reference

URL: https://www.mozilla.org/security/advisories/mfsa2026-57/

[email protected]
Source reference
Unverified legacy reference

URL: https://www.mozilla.org/security/advisories/mfsa2026-58/

[email protected]

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.