Multiple vulnerabilities in Cisco Web Security Appliance

Published: 2018-08-16

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2018-0428 CVE-2018-0410
CWE-ID	CWE-264 CWE-400
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Cisco Web 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) Privilege escalation

EUVDB-ID: #VU14427

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2018-0428

CWE-ID: CWE-264 - Permissions, Privileges, and Access Controls

Exploit availability: No

Description

The vulnerability allows a local attacker to gain elevated privileges on the target system.

The vulnerability exists in the account management subsystem of Cisco Web Security Appliance (WSA) due to improper implementation of access controls. A local attacker can authenticate to the device, escape the CLI subshell and execute system-level commands on the underlying operating system as root.

Mitigation

The vulnerability has been fixed in the versions 10.1.3-054, 10.5.2-072.

Vulnerable software versions

Cisco Web Security Appliance: 10.0.0 959 - 11.5.0 FCS 000

CPE2.3

External links

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180815-wsa-escalati...

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

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.

The attacker would have to login to the system and perform certain actions 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) Resource exhaustion

EUVDB-ID: #VU14428

Risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2018-0410

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

The vulnerability allows a remote attacker to cause DoS condition on the target system.

The vulnerability exists in the web proxy functionality of Cisco AsyncOS Software for Cisco Web Security Appliances due to improper management of memory resources for TCP connections. A remote attacker can establish a high number of TCP connections to the data interface of an affected device via IPv4 or IPv6, exhaust system memory and cause the system to stop processing new connections.