SB2016091308 - Multiple vulnerabilities in Microsoft Exchange Server

Description

This security bulletin contains information about 3 secuirty vulnerabilities.

1) Information disclosure (CVE-ID: CVE-2016-0138)

The vulnerability allows a remote authenticated attacker to obtain potentially sensitive information.

The vulnerability exists due to improper parsing of email messages. A remote attacker can send a specially crafted message using "send as" rights and gain access to confidential user information that is contained in Microsoft Outlook applications.

Successful exploitation of the vulnerability leads to information disclosure on the vulnerable system.

2) Open redirect (CVE-ID: CVE-2016-3378)

The vulnerability allows a remote attacker to perform spoofing attacks.

Open redirect vulnerability exists due to insufficient verification of URL when redirecting users to external websites. A remote attacker can create a specially crafted link, trick the victim into following it and redirect the victim to malicious website.

Successful exploitation of the vulnerability will allow to steal valid user's credentials and use the information to conduct further attacks.

3) Cross-site scripting (CVE-ID: CVE-2016-3379)

Vulnerability allows a remote authenticated attacker to perform XSS attacks.

The vulnerability is caused by an input validation error in Microsoft Exchange Server 2016 Cumulative Update 1 and 2. A remote authenticated attacker can trick the victim to follow a specially specially crafted link and execute arbitrary HTML and script code in victim's browser in security context of vulnerable website.

Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.

Remediation

Install update from vendor's website.

References

• https://technet.microsoft.com/en-us/library/security/ms16-108.aspx