Microsoft Windows up to Server 2025 WLAN Service integer underflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.3$5k-$25k0.35

Summaryinfo

A vulnerability was found in Microsoft Windows up to Server 2025. It has been classified as critical. The affected element is an unknown function of the component WLAN Service. This manipulation causes integer underflow. This vulnerability is registered as CVE-2026-83855. Remote exploitation of the attack is possible. No exploit is available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability classified as critical was found in Microsoft Windows up to Server 2025. Affected by this vulnerability is an unknown code block of the component WLAN Service. The manipulation with an unknown input leads to a integer underflow vulnerability. The CWE definition for the vulnerability is CWE-191. The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result. As an impact it is known to affect availability. The summary by CVE is:

Integer underflow (wrap or wraparound) in Windows WLAN Service allows an unauthorized attacker to deny service over a network.

It is possible to read the advisory at msrc.microsoft.com. This vulnerability is known as CVE-2026-83855 since 09/01/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/14/2026).

Applying a patch is able to eliminate this problem.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.5
VulDB Meta Temp Score: 7.3

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
CNA Vector (microsoft): 🔒

CVSSv2info

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

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
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: Patch
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/01/2026 CVE reserved
10/14/2026 +43 days Advisory disclosed
10/14/2026 +0 days VulDB entry created
10/14/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CVE: CVE-2026-83855 (🔒)
GCVE (CVE): GCVE-0-2026-83855
GCVE (VulDB): GCVE-100-419095

Entryinfo

Created: 10/14/2026 07:26
Changes: 10/14/2026 07:26 (63)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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