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CVE-2021-34714
HIGH · CVSS 7.4
EPSS exploitation probability: 0%
Published 2021-09-23T03:15:18.153 · Last modified 2026-06-17T03:56:24.637

Summary

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

Affected products

cisco — fxos

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.