Apple macOS up to 15.7/26/26.6 SMB Client out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.6$5k-$25k0.32

Summaryinfo

A vulnerability was found in Apple macOS up to 15.7/26/26.6. It has been declared as very critical. This affects an unknown function of the component SMB Client. Executing a manipulation can lead to out-of-bounds write. This vulnerability is handled as CVE-2026-84515. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability has been found in Apple macOS up to 15.7/26/26.6 and classified as very critical. This vulnerability affects some unknown processing of the component SMB Client. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. The CWE definition for the vulnerability is CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in macOS Golden Gate 27, macOS Sequoia 15.8, macOS Tahoe 26.7. Connecting to a malicious SMB server may lead to kernel memory corruption.

The advisory is available at support.apple.com. This vulnerability was named CVE-2026-84515 since 09/01/2026. The exploitation appears to be easy. The attack can be initiated remotely. Successful exploitation requires user interaction by the victim. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 09/15/2026).

Upgrading to version 15.8, 26.7 or 27 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.0
VulDB Meta Temp Score: 8.6

VulDB Base Score: 9.0
VulDB Temp Score: 8.6
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: Out-of-bounds write
CWE: CWE-787 / 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 15.8/26.7/27

Timelineinfo

09/01/2026 CVE reserved
09/14/2026 +13 days VulDB entry created
09/15/2026 +0 days Advisory disclosed
09/15/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-84515 (🔒)
GCVE (CVE): GCVE-0-2026-84515
GCVE (VulDB): GCVE-100-403906
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 09/15/2026 01:07
Changes: 09/15/2026 01:07 (56)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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