CVE-2026-43803Network attack vector

Remote system termination via CoreAudio bounds failure

Published Jul 27, 2026 · Updated Jul 27, 2026

Out-of-bounds write in CoreAudio across affected Apple operating systems allows remote attackers to cause unexpected system termination. CoreAudio writes beyond an allocated buffer because its bounds checks do not reject an unspecified remote input before the write. Apple has not disclosed the network protocol or data format; successful triggering terminates the system, with no vendor-reported data access or code execution.

CVSS severity9.8
Critical
EPSS probability0.78%
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

Out-of-bounds write in CoreAudio across affected Apple operating systems allows remote attackers to cause unexpected system termination. CoreAudio writes beyond an allocated buffer because its bounds checks do not reject an unspecified remote input before the write. Apple has not disclosed the network protocol or data format; successful triggering terminates the system, with no vendor-reported data access or code execution.

The record

CVE
CVE-2026-43803
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
Apple
Product
iOS and iPadOS
Classifications
CWE-787, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 27, 2026Record 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=0 <26.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · iOS and iPadOSversion=0 <26.6
Apple · visionOSversion=0 <26.6
Apple · tvOSversion=0 <26.6
Apple · macOSversion=0 <14.8.8; version=0 <15.7.8; version=0 <26.6
Apple · watchOSversion=0 <26.6

Published CVSS scores

9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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

CWE-787Out-of-bounds Write
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