Security Updates for Exchange (July 2019)

Medium Nessus Plugin ID 126581

Synopsis

The Microsoft Exchange Server installed on the remote host is affected by multiple vulnerabilities.

Description

The Microsoft Exchange Server installed on the remote host is missing security updates. It is, therefore, affected by multiple vulnerabilities :

- A cross-site-scripting (XSS) vulnerability exists when Microsoft Exchange Server does not properly sanitize a specially crafted web request to an affected Exchange server. An authenticated attacker could exploit the vulnerability by sending a specially crafted request to an affected server. The attacker who successfully exploited the vulnerability could then perform cross- site scripting attacks on affected systems and run script in the security context of the current user. The attacks could allow the attacker to read content that the attacker is not authorized to read, use the victim's identity to take actions on the Exchange server on behalf of the user, such as change permissions and delete content, and inject malicious content in the browser of the user. The security update addresses the vulnerability by helping to ensure that Exchange Server properly sanitizes web requests. (CVE-2019-1137)

- An information disclosure vulnerability exists when Exchange allows creation of entities with Display Names having non-printable characters. An authenticated attacker could exploit this vulnerability by creating entities with invalid display names, which, when added to conversations, remain invisible. This security update addresses the issue by validating display names upon creation in Microsoft Exchange, and by rendering invalid display names correctly in Microsoft Outlook clients.
(CVE-2019-1084)

- An elevation of privilege vulnerability exists in Microsoft Exchange Server. An attacker who successfully exploited this vulnerability could gain the same rights as any other user of the Exchange server. This could allow the attacker to perform activities such as accessing the mailboxes of other users. Exploitation of this vulnerability requires Exchange Web Services (EWS) to be enabled and in use in an affected environment.
(CVE-2019-1136)

Solution

Microsoft has released the following security updates to address this issue:
-KB4509410
-KB4509409
-KB4509408

See Also

http://www.nessus.org/u?252d2640

http://www.nessus.org/u?5a7f2f98

http://www.nessus.org/u?b960286e

Plugin Details

Severity: Medium

ID: 126581

File Name: smb_nt_ms19_jul_exchange.nasl

Version: 1.2

Type: local

Agent: windows

Published: 2019/07/09

Updated: 2019/07/12

Dependencies: 57033, 77910

Risk Information

Risk Factor: Medium

CVSS Score Source: CVE-2019-1137

CVSS v2.0

Base Score: 6.8

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P

CVSS v3.0

Base Score: 6.3

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:L

Vulnerability Information

CPE: cpe:/a:microsoft:exchange_server

Required KB Items: SMB/MS_Bulletin_Checks/Possible

Patch Publication Date: 2019/07/09

Vulnerability Publication Date: 2019/07/09

Reference Information

CVE: CVE-2019-1084, CVE-2019-1136, CVE-2019-1137

MSKB: 4509410, 4509409, 4509408

MSFT: MS19-4509410, MS19-4509409, MS19-4509408

IAVA: 2019-A-0229