Apple macOS up to 14.8.7/15.7.7/26.5 SMB memory corruption

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.2$0-$5k1.37

Summaryinfo

A vulnerability labeled as critical has been found in Apple macOS up to 14.8.7/15.7.7/26.5. Affected by this issue is some unknown functionality of the component SMB Handler. Such manipulation leads to memory corruption. This vulnerability is uniquely identified as CVE-2026-39873. The attack can be launched remotely. No exploit exists.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Apple macOS up to 14.8.7/15.7.7/26.5. Affected by this issue is an unknown part of the component SMB Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is availability. CVE summarizes:

The issue was addressed with improved memory handling. This issue is fixed in macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6. Connecting to a malicious SMB server may lead to unexpected system termination.

The advisory is available at support.apple.com. This vulnerability is handled as CVE-2026-39873 since 04/07/2026. The exploitation is known to be easy. The attack may be launched remotely. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/27/2026).

Upgrading to version 14.8.8, 15.7.8 or 26.6 eliminates this vulnerability.

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Productinfo

Type

Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: macOS 14.8.8/15.7.8/26.6

Timelineinfo

04/07/2026 CVE reserved
07/27/2026 +111 days Advisory disclosed
07/27/2026 +0 days VulDB entry created
07/27/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-39873 (🔒)
GCVE (CVE): GCVE-0-2026-39873
GCVE (VulDB): GCVE-100-383582
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 07/27/2026 22:55
Changes: 07/27/2026 22:55 (56)
Complete: 🔍
Cache ID: 216::103

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