8.6
High
CVE-2020-3566 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply updates per vendor instructions.
Ransomware campaigns
Not observed so far
Weakness
CWE-400
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.
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Cisco IOS XR Software | Versions not published |
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