Microsoft Exchange Server 2013/2016 information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

A vulnerability, which was classified as problematic, was found in Microsoft Exchange Server 2013/2016 (Groupware Software). This affects some unknown processing. The manipulation with an unknown input leads to a information disclosure vulnerability. CWE is classifying the issue as CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. This is going to have an impact on confidentiality. The summary by CVE is:

Microsoft Exchange Server 2013 and Microsoft Exchange Server 2016 allow an input sanitization issue with Microsoft Exchange that could potentially result in unintended Information Disclosure, aka "Microsoft Exchange Information Disclosure Vulnerability"

The bug was discovered 09/12/2017. The weakness was published 09/12/2017 as KB4036108 as confirmed security update guide (Website). It is possible to read the advisory at portal.msrc.microsoft.com. This vulnerability is uniquely identified as CVE-2017-11761 since 07/31/2017. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK. The advisory points out:

An input sanitization issue exists with Microsoft Exchange that could potentially result in unintended Information Disclosure. An attacker who successfully exploited the vulnerability could identify the existence of RFC1918 addresses on the local network from a client on the Internet. An attacker could use this internal host information as part of a larger attack.

The vulnerability scanner Nessus provides a plugin with the ID 103139 (Security Updates for Exchange (September 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 53009 (Microsoft Windows Exchange Server Update For September 2017).

Applying the patch KB4036108 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 (103139). Similar entry is available at 106544.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
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CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.2

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 5.3
NVD Vector: 🔍

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔍
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Exploitinginfo

Class: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
ATT&CK: T1592

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 103139
Nessus Name: Security Updates for Exchange (September 2017)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 802136
OpenVAS Name: Microsoft Exchange Server Multiple Vulnerabilities (KB4036108)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Countermeasuresinfo

Recommended: Patch
Status: 🔍

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Patch: KB4036108

Timelineinfo

07/31/2017 🔍
09/12/2017 +43 days 🔍
09/12/2017 +0 days 🔍
09/12/2017 +0 days 🔍
09/12/2017 +0 days 🔍
09/12/2017 +0 days 🔍
09/12/2017 +0 days 🔍
09/13/2017 +1 days 🔍
01/11/2021 +1216 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4036108
Researcher: Zhongcheng Li
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-11761 (🔍)
OVAL: 🔍

SecurityTracker: 1039320
SecurityFocus: 100731 - Microsoft Exchange Server CVE-2017-11761 Information Disclosure Vulnerability

See also: 🔍

Entryinfo

Created: 09/13/2017 11:44
Updated: 01/11/2021 17:47
Changes: 09/13/2017 11:44 (73), 11/15/2019 11:22 (11), 01/11/2021 17:40 (2), 01/11/2021 17:47 (1)
Complete: 🔍

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