CVE-2024-40866 — The issue was addressed with improved UI

The issue was addressed with improved UI. This issue is fixed in Safari 18, macOS Sequoia 15. Visiting a malicious website may lead to address bar spoofing.

01What is this vulnerability?

The issue was addressed with improved UI. This issue is fixed in Safari 18, macOS Sequoia 15. Visiting a malicious website may lead to address bar spoofing.

02Affected products

Vendor	Product	Versions
Apple	macOS	unspecified
Apple	Safari	unspecified

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Open the Sigma generator with a pre-filled prompt for this CVE to draft a starting detection in your stack of choice:

Open in Sigma generator →

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2024-09-16T23:22:28.243Z
• Last modified: 2025-11-04T16:13:38.887Z

09References

• support.apple.com — https://support.apple.com/en-us/121238
• support.apple.com — https://support.apple.com/en-us/121241