Two vulnerabilities in Cisco Email Security Appliance

Published: 2017-06-09

Risk	Low
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2017-6671 CVE-2017-6661
CWE-ID	CWE-20 CWE-79
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Cisco Email Security Appliance Server applications / IDS/IPS systems, Firewalls and proxy servers
Vendor	Cisco Systems, Inc

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Security bypass

EUVDB-ID: #VU6999

Risk: Low

CVSSv3.1: 5.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-6671

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

The vulnerability allows remote unauthenticated attacker to bypass configured filters on the device.

The weakness exists in the email message scanning of Cisco AsyncOS Software for Cisco Email Security Appliance (ESA) due to improper input validation of an email with an attachment and modified Multipurpose Internet Mail Extensions (MIME) header. A remote attacker can send a malformed email message with an attachment to bypass configured message filters.

Mitigation

Update to version 9.8.1-015 or 10.0.2-020.

Vulnerable software versions

Cisco Email Security Appliance: 9.7.1 066 - 10.0.1 087

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170607-esa1

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected application in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Cross-site scripting

EUVDB-ID: #VU7000

Risk: Low

CVSSv3.1: 5.3 [CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-6661

CWE-ID: CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Exploit availability: No

Description

The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.

The weakness exists in the web-based management interface due to incorrect filtration of input data. A remote attacker can trick the victim to follow a 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.