CVE-2026-6755

Impact

Mitigation bypass in the DOM: postMessage component. This vulnerability was fixed in Firefox 150 and Thunderbird 150.

Affected products

Weakness classification

References

• NVD record
• CVE.org record
• https://bugzilla.mozilla.org/show_bug.cgi?id=1880429
• https://www.mozilla.org/security/advisories/mfsa2026-30/
• https://www.mozilla.org/security/advisories/mfsa2026-33/