CVE-2020-3220 - CVE House
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Status published Medium CVE-2020-3220

Cisco IOS XE Software IPsec VPN Denial of Service Vulnerability

Vulnerability Description

A vulnerability in the hardware crypto driver of Cisco IOS XE Software for Cisco 4300 Series Integrated Services Routers and Cisco Catalyst 9800-L Wireless Controllers could allow an unauthenticated, remote attacker to disconnect legitimate IPsec VPN sessions to an affected device. The vulnerability is due to insufficient verification of authenticity of received Encapsulating Security Payload (ESP) packets. An attacker could exploit this vulnerability by tampering with ESP cleartext values as a man-in-the-middle.

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 16.4.1
Vulnerable Versions:
Unknown

Timeline

Official Publish: June 3rd, 2020
Last Modified: November 15th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-345

MITRE ATT&CK TTPs

T1557 Adversary-in-the-Middle
Credential Access
T1071 Application Layer Protocol
Command and Control
T1552 Unsecured Credentials
Credential Access
T1190 Exploit Public-Facing Application
Initial Access
T1041 Exfiltration Over C2 Channel
Exfiltration