Microsoft Lync/Skype for Business Authentication access control

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.2$0-$5k0.00

A vulnerability, which was classified as critical, was found in Microsoft Lync and Skype for Business (Unified Communication Software) (unknown version). Affected is an unknown code block of the component Authentication. The manipulation with an unknown input leads to a access control vulnerability. CWE is classifying the issue as CWE-264. This is going to have an impact on confidentiality, integrity, and availability.

The bug was discovered 10/10/2017. The weakness was disclosed 10/10/2017 as KB4011159 as confirmed security update guide (Website). The advisory is available at portal.msrc.microsoft.com. This vulnerability is traded as CVE-2017-11786 since 07/31/2017. It is possible to launch the attack remotely. The requirement for exploitation is a authentication. The technical details are unknown and an exploit is not available. This vulnerability is assigned to T1068 by the MITRE ATT&CK project. The advisory points out:

An elevation of privilege vulnerability exists when Skype for Business fails to properly handle specific authentication requests.

The vulnerability scanner Nessus provides a plugin with the ID 103753 (Security Updates for Microsoft Skype for Business and Microsoft Lync (October 2017)), 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 110306 (Microsoft Office and Microsoft Office Services and Web Apps Security Update October 2017).

Applying the patch KB4011159 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 vulnerability database at Tenable (103753). The entries 107698, 107703, 107727 and 107728 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: 7.5
VulDB Meta Temp Score: 7.4

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 8.8
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Access control
CWE: CWE-264
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 103753
Nessus Name: Security Updates for Microsoft Skype for Business and Microsoft Lync (October 2017)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 802136
OpenVAS Name: Microsoft Lync 2013 Service Pack 1 Elevation of Privilege Vulnerability (KB4011179)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: KB4011159

Timelineinfo

07/31/2017 🔍
10/10/2017 +70 days 🔍
10/10/2017 +0 days 🔍
10/10/2017 +0 days 🔍
10/10/2017 +0 days 🔍
10/10/2017 +0 days 🔍
10/11/2017 +1 days 🔍
10/13/2017 +2 days 🔍
01/16/2021 +1191 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4011159
Researcher: Jerry Decime, Hewlett Packard Enterprise
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11786 (🔍)
OVAL: 🔍

SecurityTracker: 1039530
SecurityFocus: 101156

scip Labs: https://www.scip.ch/en/?labs.20140918
See also: 🔍

Entryinfo

Created: 10/11/2017 23:38
Updated: 01/16/2021 14:55
Changes: 10/11/2017 23:38 (77), 11/23/2019 19:48 (3), 01/16/2021 14:52 (3), 01/16/2021 14:55 (3)
Complete: 🔍

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