Microsoft Windows 10/Server 2016 Device Guard Security Feature Signature 7pk security

CVSS Meta Temp Score
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CTI Interest Score
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4.8$0-$5k0.00

A vulnerability was found in Microsoft Windows 10/Server 2016 (Operating System). It has been rated as critical. This issue affects some unknown processing of the component Device Guard Security Feature. The manipulation with an unknown input leads to a 7pk security vulnerability (Signature). Using CWE to declare the problem leads to CWE-254. Impacted is confidentiality, integrity, and availability.

The bug was discovered 11/14/2017. The weakness was disclosed 11/14/2017 by James Forshaw with Google Project Zero as KB4048956 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. The identification of this vulnerability is CVE-2017-11830 since 07/31/2017. Attacking locally is a requirement. Required for exploitation is a simple authentication. Technical details are unknown but a public exploit is available. The attack technique deployed by this issue is T1211 according to MITRE ATT&CK. The advisory points out:

A security feature bypass exists when Device Guard incorrectly validates an untrusted file. An attacker who successfully exploited this vulnerability could make an unsigned file appear to be signed. Because Device Guard relies on the signature to determine the file is non-malicious, Device Guard could then allow a malicious file to execute.

The exploit is available at exploit-db.com. It is declared as proof-of-concept. We expect the 0-day to have been worth approximately $25k-$100k. The vulnerability scanner Nessus provides a plugin with the ID 104552 (KB4048956: Windows 10 LTSB November 2017 Cumulative Update), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Windows : Microsoft Bulletins and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 91414 (Microsoft Windows Security Update November 2017).

Applying the patch KB4048956 is able to eliminate this problem. The bugfix is ready for download at catalog.update.microsoft.com. A possible mitigation has been published immediately after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (104552) and Exploit-DB (43162). The entries 109334, 109335, 109336 and 109337 are pretty similar.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 4.8
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 5.3
Vendor Vector (Microsoft): 🔍

NVD Base Score: 5.3
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Name: Signature
Class: 7pk security / Signature
CWE: CWE-254
ATT&CK: T1211

Local: Yes
Remote: No

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 104552
Nessus Name: KB4048956: Windows 10 LTSB November 2017 Cumulative Update
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 880598
OpenVAS Name: Microsoft Windows Multiple Vulnerabilities (KB4048956)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Exploit-DB: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: KB4048956

Timelineinfo

07/31/2017 🔍
11/14/2017 +106 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/14/2017 +0 days 🔍
11/15/2017 +1 days 🔍
01/23/2021 +1165 days 🔍

Sourcesinfo

Vendor: microsoft.com
Product: microsoft.com

Advisory: KB4048956
Researcher: James Forshaw
Organization: Google Project Zero
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11830 (🔍)
OVAL: 🔍

SecurityTracker: 1039790
SecurityFocus: 101714 - Microsoft Windows Device Guard CVE-2017-11830 Security Bypass Vulnerability

scip Labs: https://www.scip.ch/en/?labs.20161215
See also: 🔍

Entryinfo

Created: 11/15/2017 10:33
Updated: 01/23/2021 14:41
Changes: 11/15/2017 10:33 (91), 12/06/2019 10:28 (10), 01/23/2021 14:41 (3)
Complete: 🔍

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