Vulnerability identifier: #VU28763

Vulnerability risk: Medium

CVSSv3.1: 5.9 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-3220

CWE-ID: CWE-345

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XE
Operating systems & Components / Operating system

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to disconnect legitimate IPsec VPN sessions to an affected device.

The vulnerability exists due to insufficient verification of authenticity of received Encapsulating Security Payload (ESP) packets. A remote attacker can tamper with ESP cleartext values as a man-in-the-middle and disconnect legitimate IPsec VPN sessions to an affected device.

This vulnerability affects the following products if they are running affected release of Cisco IOS XE Software: 

• Cisco ASR 1000 Series Aggregation Services Routers 
• Cisco Cloud Services Router 1000V Series 
• Cisco 4000 Series Integrated Services Routers 
• Cisco 1000 Series Integrated Services Routers

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XE: 16.12

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-vpn-dos-edOmW28Z

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.