Security restrictions bypass in Cisco Nexus 7000 Series Switches

1) Security restrictions bypass

EUVDB-ID: #VU7645

Risk: Low

CVSSv3.1: 5.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2017-6770

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

Exploit availability: No

Description

The vulnerability allows a remote attacker to bypass security restrictions.

The weakness exists in the Open Shortest Path First (OSPF) Routing Protocol Link State Advertisement (LSA) database due to improper input validation. A remote attacker can send specially crafted unicast or multicast OSPF LSA type 1 packets and take full control of the OSPF Autonomous System (AS) domain routing table, allowing the attacker to intercept or black-hole traffic.

Mitigation

The vulnerability is addressed in the following versions: 8.2(0)SK(0.129), 7.3(3)D1(0.2), 7.3(2)D1(1), 7.0(3)I7(1), 7.0(3)I7(0.430), 7.0(3)F2(2.4), 7.0(3)F2(2).

Vulnerable software versions

Cisco Nexus 7000 Series Switches: 8.0 - 8.1

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170727-ospf

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 device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.