Denial of service in Cisco IOS XR Software

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

CPE2.3

• cpe:2.3:h:cisco_systems:cisco_asr_9000_series_aggregation_services_routers:6.4.2:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_asr_9000_series_aggregation_services_routers:6.6:*:*:*:*:*:*:
• cpe:2.3:h:cisco_systems:cisco_asr_9000_series_aggregation_services_routers:6.6.3:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.0.2:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.1.4:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.2.25:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.3.15:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.4.3:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.5.3:*:*:*:*:*:*:
• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.6.25:*:*:*:*:*:*:

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

Risk: High

CVSSv3.1: 8.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H/E:H/RL:U/RC:C]

CVE-ID: CVE-2020-3569

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 IOS XR: 6.6.3

CPE2.3

• cpe:2.3:o:cisco_systems:cisco_ios_xr:6.6.3:*:*:*:*:*:*:

External links

http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dvmrp-memexh-dSmpdvfz
http://bst.cloudapps.cisco.com/bugsearch/bug/CSCvr86414

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?

Yes. This vulnerability is being exploited in the wild.