#VU1046 Denial of service in Cisco Adaptive Security Appliance (ASA) - CVE-2016-6431

Vulnerability identifier: #VU1046

Vulnerability 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-2016-6431

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco Adaptive Security Appliance (ASA)
Hardware solutions / Security hardware applicances

Vendor: Cisco Systems, Inc

Description
The vulneability allows a remote unauthenticated user to cause DoS conditions on the target system.
The weakness is due to insufficient input validation. By sending a specially crafted enrollment request to the target system via HTTPS, attackers can trigger flaw in the Certificate Authority (CA) enrollment feature that leads to the system reload.
Successful exploitation of the vulnerability results in denial of service on the vulnerable system.

Mitigation
Update to version 9.0(4.42), 9.1(7.7), 9.2(4.13), 9.3(3.11), 9.4(3.6), 9.5(3) or 9.6(1.5).

Vulnerable software versions

Cisco Adaptive Security Appliance (ASA): 8.0, 8.1, 8.2, 8.3, 8.4, 8.6, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5, 9.6

---

External links
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161019-asa-ca

---

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.