CVE-2026-43773Network attack vector

System crash via out-of-bounds HFS disk-image read

Published Jul 27, 2026 · Updated Jul 27, 2026

Out-of-bounds read in HFS in Apple macOS allows attackers to crash the system by mounting a malicious disk image. The HFS disk-image parser reads beyond input bounds because it does not adequately validate them; Apple has not identified the affected function or structure. Affected releases are macOS Sonoma before 14.8.8, Sequoia before 15.7.8, and Tahoe before 26.6; successful triggering terminates the system or corrupts kernel memory.

CVSS severity9.8
Critical
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds read in HFS in Apple macOS allows attackers to crash the system by mounting a malicious disk image. The HFS disk-image parser reads beyond input bounds because it does not adequately validate them; Apple has not identified the affected function or structure. Affected releases are macOS Sonoma before 14.8.8, Sequoia before 15.7.8, and Tahoe before 26.6; successful triggering terminates the system or corrupts kernel memory.

The record

CVE
CVE-2026-43773
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
Apple
Product
macOS
Classifications
CWE-125, 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

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Is a vulnerable build present?

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

  1. Affected versionversion=0 <14.8.8
  2. Affected versionversion=0 <15.7.8
  3. Affected versionversion=0 <26.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Apple · macOSversion=0 <14.8.8; version=0 <15.7.8; version=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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
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

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Your stack

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