High severity · published Aug 29, 2020
CVE-2020-3566
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
In wildKEV
8.6
CVSS
3.7%
EPSS
Yes
On KEV
Description
A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to exhaust process memory of an affected device. The vulnerability is due to insufficient queue management for Internet Group Management Protocol (IGMP) packets. An attacker could exploit this vulnerability by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to cause memory exhaustion, resulting in instability of other processes. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address this vulnerability.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)3.7% · higher than 90% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueMay 3, 2022
Ransomware campaign useNot known
Affected products
Which versions
CI
Cisco IOS XR Software · Cisco
All versions, or not specified · source: vendor
IX
Ios XR · Cisco
6.4.2 · source: NVD, KEV
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-3566
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-3566
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
vendor-advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dvmrp-memexh-dSmpdvfz
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