What is CVE-2023-37455?

CVE-2023-37455 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 5.4/10. Published 2023-07-12.

How severe is CVE-2023-37455?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Vulnerability in Mozilla Firefox

CVE-2023-37455

The permission request prompt from the site in the background tab was overlaid on top of the site in the foreground tab. This vulnerability affects Firefox for iOS < 115.

Published 2023-07-12 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (20.6th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 20.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Mozilla Firefox
Mozilla Firefox For iOS — versions unspecified

Weakness classification (CWE)

CWE-1021 — Improper Restriction of Rendered UI Layers or Frames (Clickjacking)

References

bugzilla.mozilla.org/show_bug.cgi (Permissions Required, Issue Tracking, Vendor Advisory)
www.mozilla.org/security/advisories/mfsa2023-25/ (Vendor Advisory)

Frequently asked questions

What is CVE-2023-37455?: CVE-2023-37455 is a medium-severity vulnerability in Mozilla Firefox, classified under Improper Restriction of Rendered UI Layers or Frames (Clickjacking). CVSS score: 5.4/10. Published 2023-07-12.
How severe is CVE-2023-37455?: Medium severity. CVSS v3 base score is 5.4 out of 10.