Remote denial of service in Cisco ASA IKE

1) Improper input validation

EUVDB-ID: #VU5672

Risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:P/RL:O/RC:C]

CVE-ID: CVE-2015-6327

CWE-ID: CWE-399 - Resource Management Errors

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper input validation within implementation of Internet Key Exchange (IKE) protocol version 1 (v1). A remote unauthenticated attacker can send specially crafted Internet Security Association and Key Management Protocol (ISAKMP) UDP packets to the affected device and cause system reboot.

Successful exploitation of the vulnerability may allow an attacker to perform a denial of service (DoS) attack.

Mitigation

Install updates from vendor's website:

Cisco ASA 7.2 - migrate to 8.2(5.58) or later
Cisco ASA 8.2 - update to 8.2(5.58) or later
Cisco ASA 8.3 - migrate to 8.4(7.29) or later
Cisco ASA 8.4 - update to 8.4(7.29)
Cisco ASA 8.5 - migrate to 9.0(4.37) or later
Cisco ASA 8.6 - migrate to 9.0(4.37) or later
Cisco ASA 8.7 - update to 8.7(1.17)
Cisco ASA 9.0 - update to 9.0(4.37)
Cisco ASA 9.1  - update to 9.1(6.8)
Cisco ASA 9.2 - update to 9.2(4)
Cisco ASA 9.3  - update to 9.3(3)

Vulnerable software versions

Cisco Adaptive Security Appliance (ASA): 7.2.1 - 9.3.2

CPE2.3

• cpe:2.3:h:cisco_systems:asa:7.2.1:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:7.2.2:*:*:*:*:*:*:*
• cpe:2.3:h:cisco_systems:asa:7.2.3:*:*:*:*:*:*:*

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20151021-asa-ike

Q & A

Can this vulnerability be exploited remotely?

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

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.