Vulnerability identifier: #VU11350

Vulnerability risk: Medium

CVSSv3.1: 7.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-0170

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XE
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

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

The weakness exists in the Cisco Umbrella Integration feature due to logic error when handling a malformed incoming packet, leading to access to an internal data structure after it has been freed. A remote attacker can send specially crafted, malformed IP packets, trigger use after free and cause the service to crash.

Mitigation
Update to versions 16.5(0.93), 16.4.1, 16.4(0.228), 16.3.3, 16.3(1.80) or 11.3(3).

Vulnerable software versions

Cisco IOS XE: 16.4.1

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-opendns-dos

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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.