CVE-2020-3569
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.
ACTIVELY EXPLOITED IN THE WILD
This vulnerability is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Cisco IOS XR
Apply updates per vendor instructions.
11/3/2021
https://nvd.nist.gov/vuln/detail/CVE-2020-3569
Vulnerability Summary
CVSS v3 Score
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CVSS v2 Score
AV:N/AC:L/Au:N/C:N/I:N/A:P
EPSS Score (Exploitation Probability)
This vulnerability has a 4.69% probability of being exploited in the next 30 days, ranking higher than 90% of all scored CVEs.
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Same Weakness Type(CWE-400, CWE-770)
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