CVE-2026-84128

Impact

Privilege escalation in the WebDriver BiDi component. This vulnerability was fixed in Firefox 155 and Thunderbird 155.

Affected products

Weakness classification

References

• NVD record
• CVE.org record
• https://bugzilla.mozilla.org/show_bug.cgi?id=2044280
• https://www.mozilla.org/security/advisories/mfsa2026-82/
• https://www.mozilla.org/security/advisories/mfsa2026-86/