Cisco NX-OS Software Unidirectional Link Detection DoS / Code Execution (cisco-sa-nxos-udld-rce-xetH6w35)

high Nessus Plugin ID 149719
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The remote device is missing a vendor-supplied security patch


An arbitrary code execution or denial of service (DoS) vulnerability exists in Unidirectional Link Detection (UDLD) feature of Cisco NX-OS Software due to insufficient input validation. An unauthenticated, adjacent attacker can exploit this issue by sending crafted Cisco UDLD protocol packets to a directly connected, affected device, to cause the device to reload, resulting in a DoS condition or arbitrary code execution.

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 CSCvv78238, CSCvv96088, CSCvv96090, CSCvv96107, CSCvw38964, CSCvw38981, CSCvw38982, CSCvw38983, CSCvw38995, CSCvw45654

See Also

Plugin Details

Severity: High

ID: 149719

File Name: cisco-sa-nxos-udld-rce-xetH6w35.nasl

Version: 1.9

Type: combined

Family: CISCO

Published: 5/19/2021

Updated: 7/26/2021

Dependencies: cisco_nxos_version.nasl, cisco_enum_smu.nasl

Risk Information

CVSS Score Source: CVE-2021-1368


Risk Factor: Medium

Score: 5.9


Risk Factor: Medium

Base Score: 4.9

Temporal Score: 3.6

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

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


Risk Factor: High

Base Score: 8.8

Temporal Score: 7.7

Vector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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-2021-1368