cvedb.io
CVE-2021-34737
MEDIUM · CVSS 5.8
EPSS exploitation probability: 0%
Published 2021-09-09T05:15:11.963 · Last modified 2026-06-17T03:56:27.617

Summary

A vulnerability in the DHCP version 4 (DHCPv4) server feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to trigger a crash of the dhcpd process, resulting in a denial of service (DoS) condition. This vulnerability exists because certain DHCPv4 messages are improperly validated when they are processed by an affected device. An attacker could exploit this vulnerability by sending a malformed DHCPv4 message to an affected device. A successful exploit could allow the attacker to cause a NULL pointer dereference, resulting in a crash of the dhcpd process. While the dhcpd process is restarting, which may take up to approximately two minutes, DHCPv4 server services are unavailable on the affected device. This could temporarily prevent network access to clients that

Affected products

cisco — ios_xr

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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.