Cisco NX-OS Software IPv6 Netstack DoS (cisco-sa-nxos-ipv6-netstack-edXPGV7K)

high Nessus Plugin ID 149310
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The remote device is missing a vendor-supplied security patch


According to its self-reported version, the network stack of Cisco NX-OS Software is affected by denial of service vulnerability due to buffers not freeing properly in the Cisco NX-OS Software network stack known as netstack. An unauthenticated, remote attacker can exploit this by sending multiple crafted IPv6 packets to an affected device. A successful exploit could cause the network stack to run out of available buffers, impairing operations of control plane and management plane protocols and resulting in a DoS condition. Manual intervention would be required to restore normal operations on the affected device.

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

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Upgrade to the relevant fixed version referenced in Cisco bug IDs CSCvu11961, CSCvu77380

See Also

Plugin Details

Severity: High

ID: 149310

File Name: cisco-sa-nxos-ipv6-netstack-edXPGV7K.nasl

Version: 1.6

Type: combined

Family: CISCO

Published: 5/6/2021

Updated: 6/3/2021

Dependencies: cisco_nxos_version.nasl

Risk Information

CVSS Score Source: CVE-2021-1387


Risk Factor: Medium

Score: 4.4


Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.2

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

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


Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

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

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

Vulnerability Information

CPE: cpe:/o:cisco:nx-os

Required KB Items: Host/Cisco/NX-OS/Version, Host/Cisco/NX-OS/Model, Host/Cisco/NX-OS/Device

Exploit Ease: No known exploits are available

Patch Publication Date: 2/24/2021

Vulnerability Publication Date: 2/24/2021

Reference Information

CVE: CVE-2021-1387

IAVA: 2021-A-0110-S

CISCO-BUG-ID: CSCvu11961, CSCvu77380

CISCO-SA: cisco-sa-nxos-ipv6-netstack-edXPGV7K

CWE: 401