CVE-2026-6755 Details
Description
Mitigation bypass in the DOM: postMessage component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.
A mitigation bypass vulnerability has been identified in the DOM: postMessage component of Mozilla Firefox. This vulnerability allows for the circumvention of existing security measures, potentially leading to unintended behavior or exploitation. It affects Firefox versions prior to 150.
Users can upgrade to Firefox 150 to address this vulnerability.
Metrics
CVSS 4.0 Severity and Vector Strings:
No CVSS 4.0 data is available for this CVE.
CVSS 3.x Severity and Vector Strings:
No data available for CVSS Version 2.0 on this CVE.
CISA-ADP
Assessed Apr 21, 2026References to Advisories, Solutions, and Tools
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| URL | Source(s) | Tag(s) |
|---|---|---|
| https://bugzilla.mozilla.org/show_bug.cgi?id=1880429 | [email protected] | Permissions Required |
| https://www.mozilla.org/security/advisories/mfsa2026-30/ | [email protected] | Vendor Advisory |
| https://www.mozilla.org/security/advisories/mfsa2026-33/ | [email protected] | Vendor Advisory |
Weakness Enumeration
| CWE-ID | CWE Name | Source |
|---|---|---|
| CWE-352 | Cross-Site Request Forgery (CSRF) | CISA-ADP |
Affected Products
| Product | Versions |
|---|---|
| mozilla firefox | < 150.0 |
CPE
Remediation
| |
| mozilla thunderbird | < 150.0 |
CPE
Remediation
| |
Change History
6 change records found show changes
| Date | Action | Recorded By |
|---|---|---|
| Jun 17, 2026 | CVE Modified | [email protected] |
| Jun 17, 2026 | CVE Modified | CISA-ADP |
| Apr 22, 2026 | Initial Analysis | [email protected] |
| Apr 22, 2026 | CVE Modified | [email protected] |
| Apr 21, 2026 | CVE Modified | CISA-ADP |
| Apr 21, 2026 | New CVE Received | [email protected] |