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CVE-2021-34714

Multiple Cisco Operating Systems Unidirectional Link Detection Denial of Service Vulnerability

Published: Sep 23, 2021Updated: Nov 21, 2024 Sources: CVE List NVD BDUCWE-20

Description

A 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.

CVSS Vector Breakdown

AV:AAC:LPR:NUI:NS:CC:NI:NA:H
Exploitability
AV:AAttack Vector
Adjacent
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:CScope
Changed
Impact
C:NConfidentiality
None
I:NIntegrity
None
A:HAvailability
High

Weaknesses

Affected Products

ciscocommercialUSNetworking Infrastructureaka cisco systems, cisco systems inc.
and 7 more affected products View all →

Attack Graph

Products CVE Techniques Tactics

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Exploitability

0 exploit sources identified

Exploit details including PoC links, Metasploit modules, and scanner templates are available after registration.

View exploit details
Official Patch Available

MITRE ATT&CK

1 technique
Initial Access
View detailed technique mapping

References

Timeline

Published
Sep 23, 2021
Last Updated
Nov 21, 2024

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