Apple iOS/iPadOS/macOS up to 26 NTLM 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$25k-$100k0.32

Summaryinfo

A vulnerability categorized as very critical has been discovered in Apple iOS, iPadOS and macOS up to 26. This affects an unknown part of the component NTLM Handler. Such manipulation leads to out-of-bounds write. This vulnerability is uniquely identified as CVE-2026-84531. The attack can be launched remotely. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Apple iOS, iPadOS and macOS up to 26. Affected by this issue is an unknown functionality of the component NTLM Handler. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. Using CWE to declare the problem leads to CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 27 and iPadOS 27, macOS Golden Gate 27. Processing maliciously crafted NTLM input may lead to unexpected app termination.

The advisory is available at support.apple.com. This vulnerability is handled as CVE-2026-84531 since 09/01/2026. The exploitation is known to be easy. The attack may be launched 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 $25k-$100k at the moment (estimation calculated on 09/15/2026).

Upgrading to version 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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💳💳💳💳💳💳
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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: iOS/iPadOS/macOS 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-2026-84531 (🔒)
GCVE (CVE): GCVE-0-2026-84531
GCVE (VulDB): GCVE-100-403922
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 09/15/2026 01:15
Changes: 09/15/2026 01:15 (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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