CVE-2020-3509 - CVE House
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Status published High CVE-2020-3509

Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers DHCP Denial of Service Vulnerability

Vulnerability Description

A vulnerability in the DHCP message handler of Cisco IOS XE Software for Cisco cBR-8 Converged Broadband Routers could allow an unauthenticated, remote attacker to cause the supervisor to crash, which could result in a denial of service (DoS) condition. The vulnerability is due to insufficient error handling when DHCP version 4 (DHCPv4) messages are parsed. An attacker could exploit this vulnerability by sending a malicious DHCPv4 message to or through a WAN interface of an affected device. A successful exploit could allow the attacker to cause a reload of the affected device. Note: On Cisco cBR-8 Converged Broadband Routers, all of the following are considered WAN interfaces: 10 Gbps Ethernet interfaces 100 Gbps Ethernet interfaces Port channel interfaces that include multiple 10 and/or 100 Gbps Ethernet interfaces

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

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Affected Vendor

Affected Software

Cisco IOS XE Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: September 24th, 2020
Last Modified: November 13th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Weaknesses (CWE)

CWE-388

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.