CVE-2023-40420Network attack vector

Denial of service via CoreAnimation memory mishandling

Published Sep 26, 2023 · Updated Nov 4, 2025

Denial of service in CoreAnimation across Apple operating systems allows remote attackers to interrupt service via crafted web content. CoreAnimation mishandles memory while processing attacker-controlled content; Apple has not disclosed the affected function or precise memory-safety failure. A victim must process the content, and the published impact is limited to service interruption, with no reported code execution or data exposure.

CVSS severity6.5
Medium
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Denial of service in CoreAnimation across Apple operating systems allows remote attackers to interrupt service via crafted web content. CoreAnimation mishandles memory while processing attacker-controlled content; Apple has not disclosed the affected function or precise memory-safety failure. A victim must process the content, and the published impact is limited to service interruption, with no reported code execution or data exposure.

The record

CVE
CVE-2023-40420
Published
Sep 26, 2023
Updated
Nov 4, 2025
Vendor
Apple
Product
iOS and iPadOS
Classifications
T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 26, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 4, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=unspecified <16.7
  2. Affected versionversion=unspecified <17

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=unspecified <16.7; version=unspecified <17
Apple · tvOSversion=unspecified <17
Apple · macOSversion=unspecified <12.7; version=unspecified <13.6; version=unspecified <14
Apple · watchOSversion=unspecified <10

Published CVSS scores

6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo