Cisco IOS XR Software IPv6 Flood DoS (cisco-sa-xripv6-spJem78K)

medium Nessus Plugin ID 147893
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The remote device is missing a vendor-supplied security patch.


According to its self-reported version, IOS-XR is affected by a denial of service vulnerability due to the software incorrectly forwarding IPv6 packets that have an IPv6 node-local multicast group destination and are received on the management interfaces. An unauthenticated, adjacent attacker can exploit this, by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination, to cause an IPv6 flood on the corresponding network, resulting in network degradation or a DoS condition.

Please see the included Cisco BID and Cisco Security Advisory for more information.


Upgrade to the relevant fixed version referenced in Cisco bug ID CSCvv45504.

See Also

Plugin Details

Severity: Medium

ID: 147893

File Name: cisco-sa-xripv6-spJem78K-iosxr.nasl

Version: 1.9

Type: combined

Family: CISCO

Published: 3/19/2021

Updated: 4/8/2021

Dependencies: cisco_ios_xr_version.nasl, cisco_enum_smu.nasl

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2021-1286


Risk Factor: Low

Score: 3.6


Risk Factor: Low

Base Score: 3.3

Temporal Score: 2.4

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

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

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

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

Vulnerability Information

CPE: cpe:/o:cisco:ios_xr

Required KB Items: Host/Cisco/IOS-XR/Version, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 2/3/2021

Vulnerability Publication Date: 2/3/2021

Reference Information

CVE: CVE-2021-1268

IAVA: 2021-A-0062


CISCO-SA: cisco-sa-xripv6-spJem78K

CWE: 1076