Denial of service in Cisco IOS XE

1) Improper input validation

EUVDB-ID: #VU9125

Risk: Low

CVSSv3.1: 7.2 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:H/RL:O/RC:C]

CVE-ID: CVE-2017-12319

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The weakness exists in the Border Gateway Protocol (BGP) over an Ethernet Virtual Private Network (EVPN) for Cisco IOS XE Software due to changes in the implementation of the BGP MPLS-Based Ethernet VPN RFC (RFC 7432) draft. A remote attacker can send a specially crafted BGP Inclusive Multicast Ethernet Tag Route or BGP EVPN MAC/IP Advertisement Route update packet, corrupt the BGP routing table and cause the device to reload.

Successful exploitation of the vulnerability results in denial of service.

Mitigation

Update to version 16.3 or later.

Vulnerable software versions

Cisco IOS XE: 15.5.3 S4.1 - 16.2.1.25

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20171103-bgp

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?

Yes. This vulnerability is being exploited in the wild.