CVE-2021-34714

Summary

CVECVE-2021-34714
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-09-23 03:15:00 UTC
Updated2023-11-07 03:36:00 UTC
DescriptionA vulnerability in the Unidirectional Link Detection (UDLD) feature of Cisco FXOS Software, Cisco IOS Software, Cisco IOS XE Software, Cisco IOS XR Software, and Cisco NX-OS Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload. This vulnerability is due to improper input validation of the UDLD packets. An attacker could exploit this vulnerability by sending specifically crafted UDLD packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. Note: The UDLD feature is disabled by default, and the conditions to exploit this vulnerability are strict. An attacker must have full control of a directly connected device. On Cisco IOS XR devices, the impact is limited to the reload of the UDLD process.

Risk And Classification

Problem Types: CWE-20

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Hardware Cisco Firepower 4100 - All All All
Hardware Cisco Firepower 4110 - All All All
Hardware Cisco Firepower 4112 - All All All
Hardware Cisco Firepower 4115 - All All All
Hardware Cisco Firepower 4120 - All All All
Hardware Cisco Firepower 4125 - All All All
Hardware Cisco Firepower 4140 - All All All
Hardware Cisco Firepower 4145 - All All All
Hardware Cisco Firepower 4150 - All All All
Hardware Cisco Firepower 9300 - All All All
Hardware Cisco Firepower 9300 Sm-24 - All All All
Hardware Cisco Firepower 9300 Sm-36 - All All All
Hardware Cisco Firepower 9300 Sm-40 - All All All
Hardware Cisco Firepower 9300 Sm-44 - All All All
Hardware Cisco Firepower 9300 Sm-44 X 3 - All All All
Hardware Cisco Firepower 9300 Sm-48 - All All All
Hardware Cisco Firepower 9300 Sm-56 - All All All
Hardware Cisco Firepower 9300 Sm-56 X 3 - All All All
Hardware Cisco Firepower 9300 With 1 Sm-24 Module - All All All
Hardware Cisco Firepower 9300 With 1 Sm-36 Module - All All All
Hardware Cisco Firepower 9300 With 1 Sm-44 Module - All All All
Hardware Cisco Firepower 9300 With 3 Sm-44 Module - All All All
Operating System Cisco Firepower Extensible Operating System All All All All
Operating System Cisco Firepower Extensible Operating System All All All All
Operating System Cisco Firepower Extensible Operating System All All All All
Operating System Cisco Firepower Extensible Operating System All All All All
Operating System Cisco Firepower Extensible Operating System All All All All
Operating System Cisco Fx-os All All All All
Operating System Cisco Fx-os All All All All
Operating System Cisco Fx-os All All All All
Operating System Cisco Fx-os All All All All
Operating System Cisco Fx-os All All All All
Operating System Cisco Fxos All All All All
Operating System Cisco Ios All All All All
Operating System Cisco Ios All All All All
Operating System Cisco Ios All All All All
Operating System Cisco Ios All All All All
Operating System Cisco Ios All All All All
Application Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Application Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Application Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Application Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Application Cisco Ios Xe All All All All
Operating System Cisco Ios Xe All All All All
Operating System Cisco Ios Xr All All All All
Operating System Cisco Ios Xr All All All All
Operating System Cisco Ios Xr All All All All
Operating System Cisco Ios Xr All All All All
Operating System Cisco Ios Xr All All All All
Hardware Cisco Mds 9000 - All All All
Hardware Cisco Mds 9100 - All All All
Hardware Cisco Mds 9132t - All All All
Hardware Cisco Mds 9134 - All All All
Hardware Cisco Mds 9140 - All All All
Hardware Cisco Mds 9148 - All All All
Hardware Cisco Mds 9148s - All All All
Hardware Cisco Mds 9148t - All All All
Hardware Cisco Mds 9200 - All All All
Hardware Cisco Mds 9216 - All All All
Hardware Cisco Mds 9216a - All All All
Hardware Cisco Mds 9216i - All All All
Hardware Cisco Mds 9222i - All All All
Hardware Cisco Mds 9250i - All All All
Hardware Cisco Mds 9396s - All All All
Hardware Cisco Mds 9396t - All All All
Hardware Cisco Mds 9500 - All All All
Hardware Cisco Mds 9506 - All All All
Hardware Cisco Mds 9509 - All All All
Hardware Cisco Mds 9513 - All All All
Hardware Cisco Mds 9700 - All All All
Hardware Cisco Mds 9706 - All All All
Hardware Cisco Mds 9710 - All All All
Hardware Cisco Mds 9718 - All All All
Hardware Cisco Nexus 3000 - All All All
Hardware Cisco Nexus 3016 - All All All
Hardware Cisco Nexus 3016q - All All All
Hardware Cisco Nexus 3048 - All All All
Hardware Cisco Nexus 3064 - All All All
Hardware Cisco Nexus 3064-32t - All All All
Hardware Cisco Nexus 3064-t - All All All
Hardware Cisco Nexus 3064-x - All All All
Hardware Cisco Nexus 3064t - All All All
Hardware Cisco Nexus 3064x - All All All
Hardware Cisco Nexus 3100 - All All All
Hardware Cisco Nexus 3100-v - All All All
Hardware Cisco Nexus 3100-z - All All All
Hardware Cisco Nexus 3100v - All All All
Hardware Cisco Nexus 31108pc-v - All All All
Hardware Cisco Nexus 31108pv-v - All All All
Hardware Cisco Nexus 31108tc-v - All All All
Hardware Cisco Nexus 31128pq - All All All
Hardware Cisco Nexus 3132c-z - All All All
Hardware Cisco Nexus 3132q - All All All
Hardware Cisco Nexus 3132q-v - All All All
Hardware Cisco Nexus 3132q-x - All All All
Hardware Cisco Nexus 3132q-xl - All All All
Hardware Cisco Nexus 3132q-x/3132q-xl - All All All
Hardware Cisco Nexus 3164q - All All All
Hardware Cisco Nexus 3172 - All All All
Hardware Cisco Nexus 3172pq - All All All
Hardware Cisco Nexus 3172pq-xl - All All All
Hardware Cisco Nexus 3172pq/pq-xl - All All All
Hardware Cisco Nexus 3172tq - All All All
Hardware Cisco Nexus 3172tq-32t - All All All
Hardware Cisco Nexus 3172tq-xl - All All All
Hardware Cisco Nexus 3200 - All All All
Hardware Cisco Nexus 3232c - All All All
Hardware Cisco Nexus 3232c - All All All
Hardware Cisco Nexus 3264c-e - All All All
Hardware Cisco Nexus 3264q - All All All
Hardware Cisco Nexus 3400 - All All All
Hardware Cisco Nexus 3408-s - All All All
Hardware Cisco Nexus 34180yc - All All All
Hardware Cisco Nexus 34200yc-sm - All All All
Hardware Cisco Nexus 3432d-s - All All All
Hardware Cisco Nexus 3464c - All All All
Hardware Cisco Nexus 3500 - All All All
Hardware Cisco Nexus 3500 Platform - All All All
Hardware Cisco Nexus 3524 - All All All
Hardware Cisco Nexus 3524-x - All All All
Hardware Cisco Nexus 3524-xl - All All All
Hardware Cisco Nexus 3524-x/xl - All All All
Hardware Cisco Nexus 3548 - All All All
Hardware Cisco Nexus 3548-x - All All All
Hardware Cisco Nexus 3548-xl - All All All
Hardware Cisco Nexus 3548-x/xl - All All All
Hardware Cisco Nexus 3600 - All All All
Hardware Cisco Nexus 36180yc-r - All All All
Hardware Cisco Nexus 3636c-r - All All All
Hardware Cisco Nexus 5000 - All All All
Hardware Cisco Nexus 5010 - All All All
Hardware Cisco Nexus 5020 - All All All
Hardware Cisco Nexus 5500 - All All All
Hardware Cisco Nexus 5548p - All All All
Hardware Cisco Nexus 5548up - All All All
Hardware Cisco Nexus 5596t - All All All
Hardware Cisco Nexus 5596up - All All All
Hardware Cisco Nexus 5600 - All All All
Hardware Cisco Nexus 56128p - All All All
Hardware Cisco Nexus 5624q - All All All
Hardware Cisco Nexus 5648q - All All All
Hardware Cisco Nexus 5672up - All All All
Hardware Cisco Nexus 5672up-16g - All All All
Hardware Cisco Nexus 5696q - All All All
Hardware Cisco Nexus 6000 - All All All
Hardware Cisco Nexus 6001 - All All All
Hardware Cisco Nexus 6001p - All All All
Hardware Cisco Nexus 6001t - All All All
Hardware Cisco Nexus 6004 - All All All
Hardware Cisco Nexus 6004x - All All All
Hardware Cisco Nexus 7000 - All All All
Hardware Cisco Nexus 7000 10-slot - All All All
Hardware Cisco Nexus 7000 18-slot - All All All
Hardware Cisco Nexus 7000 4-slot - All All All
Hardware Cisco Nexus 7000 9-slot - All All All
Hardware Cisco Nexus 7000 Supervisor 1 - All All All
Hardware Cisco Nexus 7000 Supervisor 2 - All All All
Hardware Cisco Nexus 7000 Supervisor 2e - All All All
Hardware Cisco Nexus 7004 - All All All
Hardware Cisco Nexus 7009 - All All All
Hardware Cisco Nexus 7010 - All All All
Hardware Cisco Nexus 7018 - All All All
Hardware Cisco Nexus 7700 - All All All
Hardware Cisco Nexus 7700 10-slot - All All All
Hardware Cisco Nexus 7700 18-slot - All All All
Hardware Cisco Nexus 7700 2-slot - All All All
Hardware Cisco Nexus 7700 6-slot - All All All
Hardware Cisco Nexus 7700 Supervisor 2e - All All All
Hardware Cisco Nexus 7700 Supervisor 3e - All All All
Hardware Cisco Nexus 7702 - All All All
Hardware Cisco Nexus 7706 - All All All
Hardware Cisco Nexus 7710 - All All All
Hardware Cisco Nexus 7718 - All All All
Hardware Cisco Nexus 9000 - All All All
Hardware Cisco Nexus 9000v - All All All
Hardware Cisco Nexus 9000 In Aci Mode - All All All
Hardware Cisco Nexus 9000 In Standalone - All All All
Hardware Cisco Nexus 9000 In Standalone Nx-os Mode - All All All
Hardware Cisco Nexus 9200 - All All All
Hardware Cisco Nexus 92160yc-x - All All All
Hardware Cisco Nexus 9221c - All All All
Hardware Cisco Nexus 92300yc - All All All
Hardware Cisco Nexus 92304qc - All All All
Hardware Cisco Nexus 92348gc-x - All All All
Hardware Cisco Nexus 9236c - All All All
Hardware Cisco Nexus 9272q - All All All
Hardware Cisco Nexus 9300 - All All All
Hardware Cisco Nexus 93108tc-ex - All All All
Hardware Cisco Nexus 93108tc-ex-24 - All All All
Hardware Cisco Nexus 93108tc-fx - All All All
Hardware Cisco Nexus 93108tc-fx-24 - All All All
Hardware Cisco Nexus 93108tc-fx3p - All All All
Hardware Cisco Nexus 93120tx - All All All
Hardware Cisco Nexus 93128 - All All All
Hardware Cisco Nexus 93128tx - All All All
Hardware Cisco Nexus 9316d-gx - All All All
Hardware Cisco Nexus 93180lc-ex - All All All
Hardware Cisco Nexus 93180tc-ex - All All All
Hardware Cisco Nexus 93180yc-ex - All All All
Hardware Cisco Nexus 93180yc-ex-24 - All All All
Hardware Cisco Nexus 93180yc-fx - All All All
Hardware Cisco Nexus 93180yc-fx-24 - All All All
Hardware Cisco Nexus 93180yc-fx3 - All All All
Hardware Cisco Nexus 93180yc-fx3s - All All All
Hardware Cisco Nexus 93216tc-fx2 - All All All
Hardware Cisco Nexus 93240yc-fx2 - All All All
Hardware Cisco Nexus 9332c - All All All
Hardware Cisco Nexus 9332pq - All All All
Hardware Cisco Nexus 93360yc-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2 - All All All
Hardware Cisco Nexus 9336c-fx2-e - All All All
Hardware Cisco Nexus 9336pq - All All All
Hardware Cisco Nexus 9336pq Aci Spine - All All All
Hardware Cisco Nexus 9348gc-fxp - All All All
Hardware Cisco Nexus 93600cd-gx - All All All
Hardware Cisco Nexus 9364c - All All All
Hardware Cisco Nexus 9364c-gx - All All All
Hardware Cisco Nexus 9372px - All All All
Hardware Cisco Nexus 9372px-e - All All All
Hardware Cisco Nexus 9372tx - All All All
Hardware Cisco Nexus 9372tx-e - All All All
Hardware Cisco Nexus 9396px - All All All
Hardware Cisco Nexus 9396tx - All All All
Hardware Cisco Nexus 9500 - All All All
Hardware Cisco Nexus 9500r - All All All
Hardware Cisco Nexus 9500 Supervisor A - All All All
Hardware Cisco Nexus 9500 Supervisor A - All All All
Hardware Cisco Nexus 9500 Supervisor B - All All All
Hardware Cisco Nexus 9500 Supervisor B - All All All
Hardware Cisco Nexus 9504 - All All All
Hardware Cisco Nexus 9508 - All All All
Hardware Cisco Nexus 9516 - All All All
Operating System Cisco Nx-os All All All All
Operating System Cisco Nx-os All All All All
Operating System Cisco Nx-os All All All All
Operating System Cisco Nx-os All All All All
Hardware Cisco Ucs 6200 - All All All
Hardware Cisco Ucs 6248up - All All All
Hardware Cisco Ucs 6248 Up Fabric Interconnect - All All All
Hardware Cisco Ucs 6296up - All All All
Hardware Cisco Ucs 6296 Up Fabric Interconnect - All All All
Hardware Cisco Ucs 6300 - All All All
Hardware Cisco Ucs 6324 - All All All
Hardware Cisco Ucs 6324 Fabric Interconnect - All All All
Hardware Cisco Ucs 6332 - All All All
Hardware Cisco Ucs 6332-16up - All All All
Hardware Cisco Ucs 6332-16up Fabric Interconnect - All All All
Hardware Cisco Ucs 6332 Fabric Interconnect - All All All
Hardware Cisco Ucs 6400 - All All All
Hardware Cisco Ucs 6454 - All All All

References

ReferenceSourceLinkTags
Multiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerability CISCO tools.cisco.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Legacy QID Mappings

  • 317061 Cisco Internetwork Operating System (IOS) Unidirectional Link Detection Denial of Service (DoS) Vulnerability (cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ)
  • 317064 Cisco Nexus Operating System (NX-OS) Unidirectional Link Detection Denial of Service (DoS) Vulnerability (cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ)
  • 317065 Cisco Internetwork Operating System (IOS) XR Unidirectional Link Detection Denial of Service (DoS) Vulnerability (cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ)
  • 317066 Cisco Unified Computing System (UCS) Fabric Interconnect Unidirectional Link Detection Denial of Service (DoS) Vulnerability (cisco-sa-ios-nxos-xr-udld-dos-W5hGHgtQ)
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