Microsoft Exchange Server 2010 SP3/2013 CU16/2013 SP3/2016 CU5 redirect

CVSS Meta Temp Score
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CTI Interest Score
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5.9$0-$5k0.00

Summaryinfo

A vulnerability categorized as problematic has been discovered in Microsoft Exchange Server 2010 SP3/2013 CU16/2013 SP3/2016 CU5. This affects an unknown part. Executing a manipulation can lead to redirect. This vulnerability appears as CVE-2017-8621. The attack may be performed from remote. There is no available exploit. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability has been found in Microsoft Exchange Server 2010 SP3/2013 CU16/2013 SP3/2016 CU5 (Groupware Software) and classified as critical. This vulnerability affects an unknown functionality. The manipulation with an unknown input leads to a redirect vulnerability. The CWE definition for the vulnerability is CWE-601. A web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a Redirect. This simplifies phishing attacks. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

Microsoft Exchange Server 2010 SP3, Exchange Server 2013 SP3, Exchange Server 2013 CU16, and Exchange Server 2016 CU5 allows an open redirect vulnerability that could lead to spoofing, aka "Microsoft Exchange Open Redirect Vulnerability".

The bug was discovered 07/11/2017. The weakness was presented 07/11/2017 with Microsoft as KB4018588 as confirmed security update guide (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability was named CVE-2017-8621 since 05/03/2017. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1204.001. The advisory points out:

An open redirect vulnerability exists in Microsoft Exchange that could lead to spoofing. To exploit the vulnerability, an attacker could send a link that has a specially crafted URL, and convince the user to click the link. When an authenticated Exchange user clicks the link, the authenticated user's browser session could be redirected to a malicious site that is designed to impersonate a legitimate website. By doing so, the attacker could trick the user and potentially acquire sensitive information, such as the user's credentials.

The vulnerability scanner Nessus provides a plugin with the ID 101522 (KB4018588: Security Update for Microsoft Exchange Server), 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 53008 (Microsoft Windows Exchange Server Update For July 2017).

Applying the patch KB4018588 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 (101522) and SecurityFocus (BID 99533†). See VDB-103425 and VDB-103426 for similar entries. Once again VulDB remains the best source for vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.2
VulDB Meta Temp Score: 6.0

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

NVD Base Score: 6.1
NVD Vector: 🔍

CVSSv2info

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

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Exploitinginfo

Class: Redirect
CWE: CWE-601
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 101522
Nessus Name: KB4018588: Security Update for Microsoft Exchange Server
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 802136
OpenVAS Name: Microsoft Exchange Server Multiple Vulnerabilities (KB4018588)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
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Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

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

Patch: KB4018588

Timelineinfo

05/03/2017 🔍
07/11/2017 +69 days 🔍
07/11/2017 +0 days 🔍
07/11/2017 +0 days 🔍
07/11/2017 +0 days 🔍
07/11/2017 +0 days 🔍
07/12/2017 +1 days 🔍
07/13/2017 +1 days 🔍
01/01/2021 +1268 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: KB4018588
Researcher: Microsoft
Organization: Microsoft
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-8621 (🔍)
GCVE (CVE): GCVE-0-2017-8621
GCVE (VulDB): GCVE-100-103468

OVAL: 🔍

SecurityFocus: 99533 - Microsoft Exchange Server CVE-2017-8621 Open Redirection Vulnerability
SecurityTracker: 1038852

See also: 🔍

Entryinfo

Created: 07/12/2017 10:51
Updated: 01/01/2021 08:39
Changes: 07/12/2017 10:51 (81), 10/25/2019 09:23 (5), 01/01/2021 08:35 (3), 01/01/2021 08:39 (1)
Complete: 🔍
Cache ID: 216::103

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