Microsoft Windows up to Server 2019 NTFS integer underflow

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.8$5k-$25k0.00

Summaryinfo

A vulnerability marked as very critical has been reported in Microsoft Windows. Affected by this vulnerability is an unknown functionality of the component NTFS. The manipulation leads to an unknown weakness. This vulnerability is referenced as CVE-2021-31956. Remote exploitation of the attack is possible. Furthermore, an exploit is available. It is recommended to apply a patch to fix this issue.

Detailsinfo

A vulnerability was found in Microsoft Windows (Operating System) and classified as very critical. This issue affects an unknown code of the component NTFS. Using CWE to declare the problem leads to 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. Impacted is confidentiality, integrity, and availability.

The weakness was published 06/08/2021 as confirmed security guidance (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The identification of this vulnerability is CVE-2021-31956. Technical details are unknown but an exploit is available. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 09/15/2024).

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Zero-Day.cz (636). Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

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Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.1
VulDB Meta Temp Score: 7.8

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

Vendor Base Score (Microsoft): 7.8
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector (Microsoft): 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Integer underflow
CWE: CWE-191 / CWE-189
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Zero-Day.cz: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

04/30/2021 🔍
06/08/2021 +39 days 🔍
06/08/2021 +0 days 🔍
06/09/2021 +0 days 🔍
09/15/2024 +1194 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed

CVE: CVE-2021-31956 (🔍)
GCVE (CVE): GCVE-0-2021-31956
GCVE (VulDB): GCVE-100-176495
scip Labs: https://www.scip.ch/en/?labs.20161215

Entryinfo

Created: 06/09/2021 06:49
Updated: 09/15/2024 13:07
Changes: 06/09/2021 06:49 (33), 06/09/2021 06:53 (22), 06/10/2021 20:25 (2), 04/21/2024 19:33 (29), 06/27/2024 17:57 (2), 07/29/2024 22:36 (27), 09/15/2024 13:07 (1)
Complete: 🔍
Cache ID: 216::103

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

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