Security restrictions bypass in Cisco Web Security Appliance

1) Security restrictions bypass

EUVDB-ID: #VU1088

Risk: Low

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-1480

CWE-ID: CWE-388 - Error Handling

Exploit availability: No

Description

The vulnerability allows a remote unauthenticated user to bypass security restrictions on the target system.
The weakness exists due to improper error handling. By sending an email message with a specially crafted MIME attachment, a remote attacker can bypass the configured user filters.
Successful exploitation of the vulnerability allows a malicious user to gain access to the vulnerable system.

Mitigation

Update to version 9.1.1-038, 9.7.1-066.

Vulnerable software versions

Cisco Web Security Appliance: 9.5.0 444

Cisco Email Security Appliance: 8.0.0 000 - 9.6.0 042

CPE2.3

• cpe:2.3:a:cisco_systems:cisco_web_security_appliance:9.5.0 444:*:*:*:*:*:*:*
• cpe:2.3:a:cisco_systems:cisco_email_security_appliance:8.0.0 000:*:*:*:*:*:*:*
• cpe:2.3:a:cisco_systems:cisco_email_security_appliance:8.5.6 106:*:*:*:*:*:*:*
• cpe:2.3:a:cisco_systems:cisco_email_security_appliance:9.0.0 000:*:*:*:*:*:*:*

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161026-esawsa1

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.