CVE-2020-3500 - CVE House
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Status published Medium CVE-2020-3500

Cisco StarOS IPv6 Denial of Service Vulnerability

Vulnerability Description

A vulnerability in the IPv6 implementation of Cisco StarOS could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. The vulnerability is due to insufficient validation of incoming IPv6 traffic. An attacker could exploit this vulnerability by sending a crafted IPv6 packet to an affected device with the goal of reaching the vulnerable section of the input buffer. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. This vulnerability is specific to IPv6 traffic. IPv4 traffic 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

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Affected Vendor

Affected Software

Cisco ASR 5000 Series Software
Vulnerable Versions:
Unknown

Timeline

Official Publish: August 17th, 2020
Last Modified: November 13th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H

Weaknesses (CWE)

CWE-119

MITRE ATT&CK TTPs

T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1203 Exploitation for Client Execution
Execution
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control