CVE-2023-40403 — The issue was addressed with improved memory handling

The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.6, tvOS 17, iOS 16.7 and iPadOS 16.7, macOS Monterey 12.7, watchOS 10, iOS 17 and iPadOS 17, macOS Sonoma 14. Processing web content may disclose sensitive information.

01What is this vulnerability?

The issue was addressed with improved memory handling. This issue is fixed in macOS Ventura 13.6, tvOS 17, iOS 16.7 and iPadOS 16.7, macOS Monterey 12.7, watchOS 10, iOS 17 and iPadOS 17, macOS Sonoma 14. Processing web content may disclose sensitive information.

02Affected products

Vendor	Product	Versions
Apple	iOS and iPadOS	unspecified
Apple	macOS	unspecified
Apple	iOS and iPadOS	unspecified
Apple	macOS	unspecified
Apple	tvOS	unspecified
Apple	macOS	unspecified
Apple	watchOS	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: 2023-09-26T20:14:54.697Z
• Last modified: 2025-11-04T19:18:23.582Z

09References

• support.apple.com — https://support.apple.com/en-us/HT213938
• support.apple.com — https://support.apple.com/en-us/HT213932
• support.apple.com — https://support.apple.com/en-us/HT213927
• support.apple.com — https://support.apple.com/en-us/HT213931
• support.apple.com — https://support.apple.com/en-us/HT213936
• support.apple.com — https://support.apple.com/en-us/HT213940
• support.apple.com — https://support.apple.com/en-us/HT213937
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/5
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/10
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/6
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/8
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/9
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/3
• seclists.org — http://seclists.org/fulldisclosure/2023/Oct/4