CVE-2020-3569

Cisco IOS XR: Software DVMRP Memory Exhaustion

As of , CVE-2020-3569 in Cisco IOS XR is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch soon.

Exploited
Yes: CISA listed it on 3 November 2021
US federal deadline
3 May 2022181 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.03Higher than 88% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

Cisco IOS XR Distance Vector Multicast Routing Protocol (DVMRP) incorrectly handles Internet Group Management Protocol (IGMP) packets. Exploitation could allow an unauthenticated, remote attacker to immediately crash the IGMP process or make it consume available memory and eventually crash.

CISA's description

Multiple vulnerabilities in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to either immediately crash the Internet Group Management Protocol (IGMP) process or make it consume available memory and eventually crash. The memory consumption may negatively impact other processes that are running on the device. These vulnerabilities are due to the incorrect handling of IGMP packets. An attacker could exploit these vulnerabilities by sending crafted IGMP traffic to an affected device. A successful exploit could allow the attacker to immediately crash the IGMP process or cause memory exhaustion, resulting in other processes becoming unstable. These processes may include, but are not limited to, interior and exterior routing protocols. Cisco will release software updates that address these vulnerabilities.

The CVE record's description, from cisco

CVE published
23 September 2020
Assigned by
cisco
CVSS
8.6 High (CVSS 3.1, from the CNA)
CWE-400
Uncontrolled Resource Consumption
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
partial

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

IOS XR: other exploited entries

VulnerabilityProductOur groupListedDeadlineEPSS
CVE-2022-20821Open PortCisco IOS XRPatch soon0.11
CVE-2020-3118Software Discovery Protocol Format StringCisco IOS XRPatch soon0.12
CVE-2010-3035Border Gateway Protocol (BGP) Denial-of-ServiceCisco IOS XRPatch soon0.06
CVE-2020-3566Software DVMRP Memory ExhaustionCisco IOS XRPatch soon0.04
CVE-2009-2055Border Gateway Protocol (BGP) Denial-of-ServiceCisco IOS XRPatch soon0.03

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