Cisco IOS XR < 6.1.1 on ASR 9000 LPTS DoS

high Nessus Plugin ID 91321


The remote device is missing a vendor-supplied security patch.


The version of Cisco IOS XR running on the remote ASR 9000 device is prior to 6.1.1. It is, therefore, affected by a denial of service vulnerability in the Local Packet Transport Services (LPTS) network stack due to improper handling of flow base entries, in which too many known entries for a protocol can be created, resulting in dropping existing or new sessions. An unauthenticated, remote attacker can exploit this to cause an exhaustion of resources by sending continuous connection attempts to open TCP ports.


Upgrade to the relevant fixed version referenced in Cisco bug ID CSCux95576

See Also

Plugin Details

Severity: High

ID: 91321

File Name: cisco-sa-20160519-iosxr.nasl

Version: 1.6

Type: combined

Family: CISCO

Published: 5/25/2016

Updated: 4/8/2021

Supported Sensors: Nessus

Risk Information


Risk Factor: Low

Score: 3.6


Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2016-1407


Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:cisco:ios_xr

Required KB Items: Host/Cisco/IOS-XR/Version

Exploit Ease: No known exploits are available

Patch Publication Date: 5/19/2016

Vulnerability Publication Date: 5/19/2016

Reference Information

CVE: CVE-2016-1407

CISCO-SA: cisco-sa-20160519-ios-xr