VDB-434729 · CVE-2026-108421 · GCVE-0-2026-108421

Microsoft Windows Server 2016/Server 2019/Server 2022/Server 2025 File Server Resource Management Service out-of-bounds

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.
8.5	$5k-$25k	0.00+

Summaryinfo

A vulnerability, which was classified as very critical, has been found in Microsoft Windows Server 2016/Server 2019/Server 2022/Server 2025. This impacts an unknown function of the component File Server Resource Management Service. The manipulation leads to out-of-bounds. This vulnerability is traded as CVE-2026-108421. It is possible to initiate the attack remotely. There is no exploit available. 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 Server 2016/Server 2019/Server 2022/Server 2025. This issue affects an unknown functionality of the component File Server Resource Management Service. The manipulation with an unknown input leads to a out-of-bounds vulnerability. Using CWE to declare the problem leads to CWE-125. The product reads data past the end, or before the beginning, of the intended buffer. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

Out-of-bounds read in Windows File Server Resource Management Service allows an unauthorized attacker to elevate privileges over a network.

The advisory is shared at msrc.microsoft.com. The identification of this vulnerability is CVE-2026-108421 since 10/09/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. 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 11/10/2026).

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: 8.8
VulDB Meta Temp Score: 8.5

VulDB Base Score: 10.0
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.5
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: Out-of-bounds
CWE: CWE-125 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

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

10/09/2026 CVE reserved
11/10/2026 +32 days Advisory disclosed
11/10/2026 +0 days VulDB entry created
11/10/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: msrc.microsoft.com
Status: Confirmed

CNA: microsoft
CVE: CVE-2026-108421 (🔒)

GCVE (CVE): GCVE-0-2026-108421
GCVE (VulDB): GCVE-100-434729

Entryinfo

Created: 11/10/2026 22:03
Changes: 11/10/2026 22:03 (63)
Complete: 🔍
Cache ID: 216::103