CVE-2026-74978

CVE-2026-74978

Clickjacking issue in the Widget component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

CVSS v3 metric

CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N.

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-74978?
CVE-2026-74978 is a high-severity vulnerability, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 8.1/10. Published 2026-08-18.
How severe is CVE-2026-74978?
High severity. CVSS v3 base score is 8.1 out of 10.