VDB-419033 · CVE-2026-83840 · GCVE-0-2026-83840

Microsoft Windows up to Server 2025 Error Reporting improper authorization

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
8.1	$5k-$25k	1.82

Summaryinfo

A vulnerability classified as very critical has been found in Microsoft Windows. Affected is an unknown function of the component Error Reporting. The manipulation leads to improper authorization. This vulnerability is listed as CVE-2026-83840. The attack must be carried out locally. There is no available exploit. It is suggested to install a patch to address this issue.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Microsoft Windows. This issue affects some unknown processing of the component Error Reporting. The manipulation with an unknown input leads to a improper authorization vulnerability. Using CWE to declare the problem leads to CWE-285. The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Weak authentication in Windows Error Reporting allows an authorized attacker to elevate privileges locally.

The advisory is shared at msrc.microsoft.com. The identification of this vulnerability is CVE-2026-83840 since 09/01/2026. The exploitation is known to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 10/14/2026). MITRE ATT&CK project uses the attack technique T1548.002 for this issue.

Applying a patch is able to eliminate this problem.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

Operating System

Vendor

Microsoft

Name

Windows

Version

License

commercial

Website

Vendor: https://www.microsoft.com/
Product: https://www.microsoft.com/en-us/windows

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.3
VulDB Meta Temp Score: 8.1

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.8
CNA Vector (microsoft): 🔒

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

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

Exploitinginfo

Class: Improper authorization
CWE: CWE-285 / CWE-266
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

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-2026-83840 (🔒)
GCVE (CVE): GCVE-0-2026-83840
GCVE (VulDB): GCVE-100-419033
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 10/14/2026 06:11
Changes: 10/14/2026 06:11 (63)
Complete: 🔍
Cache ID: 216::103