A vulnerability in the DHCP version 4 (DHCPv4) server feature...

5.3 CVSS

Vulnerability Description

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 crash of the dhcpd process. While the dhcpd process is restarting, which may take approximately two minutes, DHCPv4 server services are unavailable on the affected device. This could temporarily prevent network access to clients that join the network during that time period and rely on the DHCPv4 server of the affected device. Notes: Only the dhcpd process crashes and eventually restarts automatically. The router does not reload. This vulnerability only applies to DHCPv4. DHCP version 6 (DHCPv6) is not affected.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dhcp-dos-3tgPKRdm

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Affected Vendor

Cisco

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Affected Software

Cisco IOS XR Software

Vulnerable Versions:

5.2.0, 5.2.1, 5.2.2, 5.2.4, 5.2.3, 5.2.5, 5.2.47, 5.3.0, 5.3.1, 5.3.2, 5.3.3, 5.3.4, 6.0.0, 6.0.1, 6.0.2, 6.1.1, 6.1.2, 6.1.3, 6.1.4, 6.1.12, 6.1.22, 6.1.32, 6.1.36, 6.1.42, 6.2.1, 6.2.2, 6.2.3, 6.2.25, 6.2.11, 6.3.2, 6.3.3, 6.3.15, 6.4.1, 6.4.2, 6.4.3, 6.5.1, 6.5.2, 6.5.3, 6.5.25, 6.5.26, 6.5.28, 6.5.29, 6.5.32, 6.5.33, 6.6.2, 6.6.3, 6.6.25, 6.6.4, 7.0.1, 7.0.2, 7.0.12, 7.0.14, 7.1.1, 7.1.15, 7.1.2, 7.1.3, 6.7.1, 6.7.2, 6.7.3, 6.7.4, 7.2.0, 7.2.1, 7.2.2, 7.3.1, 7.3.15, 7.3.2, 7.3.3, 7.3.5, 7.4.1, 7.4.2, 6.8.1, 6.8.2, 7.5.1, 7.5.3, 7.5.2, 7.5.4, 7.5.5, 7.6.1, 7.6.2, 7.7.1, 7.7.2, 7.7.21, 6.9.1, 6.9.2, 7.8.1, 7.8.2, 7.9.1, 7.9.2, 7.9.21, 7.10.1, 7.10.2