Denial of service in Cisco IOS XR Software

Published: 2020-08-29 | Updated: 2020-09-02

Risk	High
Patch available	NO
Number of vulnerabilities	2
CVE-ID	CVE-2020-3566 CVE-2020-3569
CWE-ID	CWE-400
Exploitation vector	Network
Public exploit	Vulnerability #1 is being exploited in the wild. Vulnerability #2 is being exploited in the wild.
Vulnerable software Subscribe	Cisco ASR 9000 Series Aggregation Services Routers Hardware solutions / Routers & switches, VoIP, GSM, etc Cisco IOS XR Operating systems & Components / Operating system
Vendor	Cisco Systems, Inc

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

Updated: 01.09.2020

Added vulnerability #2.

1) Resource exhaustion

EUVDB-ID: #VU46126

Risk: High

CVSSv3.1: 7.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:U/RL:U/RC:C]

CVE-ID: CVE-2020-3566

CWE-ID: CWE-400 - Resource exhaustion

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient queue management for Internet Group Management Protocol (IGMP) packets in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software. A remote attacker can trigger resource exhaustion by sending crafted IGMP traffic to the affected device and perform a denial of service (DoS) attack.

Note: this vulnerability is being actively exploited in the wild.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Cisco ASR 9000 Series Aggregation Services Routers: 6.4.2 - 7.0

Cisco IOS XR: 6.0.1 - 7.3.1

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dvmrp-memexh-dSmpdvfz
http://bst.cloudapps.cisco.com/bugsearch/bug/CSCvv54838

Q & A

Can this vulnerability be exploited remotely?

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

How the attacker can exploit this vulnerability?

The attacker would have to send a specially crafted request to the affected device in order to exploit this vulnerability.

Is there known malware, which exploits this vulnerability?

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

2) Resource exhaustion

EUVDB-ID: #VU46200