CVE-2020-3566
published 2020-08-29CVE-2020-3566: A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote attacker to…
PriorityP180high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
KEVITW
CISA Known Exploited Vulnerabilitydue 2022-05-03
Exploited in the wild
EPSS
3.63%
88.3th percentile
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
3 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| cisco | cisco_ios_xr_software | — | — |
| cisco | ios_xr | — | — |
| cisco | ios_xr | — | — |
Detection & IOCsextracted from sources · hover to see the quote
- →Check for multicast routing enabled on any interface — devices with active multicast routing interfaces are vulnerable. Run 'show igmp interface'; non-empty output indicates exposure. ↗
- →Monitor for anomalous IGMP traffic volume toward Cisco IOS XR devices; exploitation manifests as IGMP process memory exhaustion or crash, potentially destabilizing interior/exterior routing protocols. ↗
- →Exploitation is unauthenticated and remote; look for high-rate inbound IGMP/DVMRP packets on multicast-enabled interfaces as an exploitation indicator. ↗
- →Track Cisco Bug IDs CSCvr86414 and CSCvv54838 / CSCvv60110 for patch applicability checks in asset management and vulnerability scanning. ↗
- ·Only Cisco IOS XR devices with multicast routing actively configured on at least one interface are vulnerable; devices without multicast routing enabled are NOT affected. ↗
- ·The IGMP rate-limiting mitigation reduces exploitation speed but does NOT prevent exploitation; it only increases the time required for a successful attack. ↗
- ·Cisco confirmed there are no workarounds that fully address these vulnerabilities; only mitigations and software updates (SMUs) are available. ↗
CVSS provenance
nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
nvdv2.07.8HIGHAV:N/AC:L/Au:N/C:N/I:N/A:C
vulncheck8.6HIGH
cisa8.6HIGH
vendor_cisco8.6HIGH
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CISA
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
cisa·2021-11-03·CVSS 8.6
CVE-2020-3566 [HIGH] CWE-400 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Vulnerability: Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Affected: Cisco IOS XR
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.
Required Action: Apply updates per vendor instructions.
Notes: https://nvd.nist.gov/vuln/detail/CVE-2020-3566
Remediation Due Date: 2022-05-03
Cisco
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
vendor_cisco·2020-08-29·CVSS 8.6
CVE-2020-3566 [HIGH] CWE-400 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
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. The
Cisco
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
vendor_cisco·CVSS 3.1
CVE-2020-3566 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
CVE-2020-3566: Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerabilities
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
GHSA
GHSA-mr9v-hqxh-vq2j: A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote atta
ghsa_unreviewed·2022-05-24
CVE-2020-3566 [HIGH] CWE-400 GHSA-mr9v-hqxh-vq2j: A vulnerability in the Distance Vector Multicast Routing Protocol (DVMRP) feature of Cisco IOS XR Software could allow an unauthenticated, remote atta
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.
VulnCheck
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
vulncheck·2020·CVSS 8.6
CVE-2020-3566 [HIGH] CWE-400 Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
Cisco IOS XR Software DVMRP Memory Exhaustion Vulnerability
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.
Affected: Cisco IOS XR
Required Action: Apply updates per vendor instructions.
Exploitation References: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxr-dvmrp-memexh-dSmpdvfz; https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json
Remediation Due: 2022-05-03
No detection rules found.
No public exploits indexed.
Tenable
One Year Later: What Can We Learn from Zerologon?
blogs_tenable·2021-08-11
One Year Later: What Can We Learn from Zerologon?
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7th September – Threat Intelligence Bulletin
blogs_checkpoint·2020-09-07
CVE-2020-3566 7th September – Threat Intelligence Bulletin
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Tenable
CVE-2020-3566, CVE-2020-3569: Zero-Day Vulnerabilities in Cisco IOS XR Software Targeted in the Wild
blogs_tenable·2020-09-01·CVSS 8.6
[HIGH] CVE-2020-3566, CVE-2020-3569: Zero-Day Vulnerabilities in Cisco IOS XR Software Targeted in the Wild
## Cloud Exposure
Tenable Cloud Security (CNAPP) Request a demo
Tenable Cloud Vulnerability Management Request a demo
Tenable CIEM Request a demo
Secure your cloud
## Vulnerability Exposure
Tenable Vulnerability Management Try for free
Tenable Security Center Request a demo
Tenable Web App Scanning Try for free
Tenable Patch Management Request a demo
Tenable Enclave Security Request a demo
Tenable Attack Surface Management Request a demo
Tenable Nessus Try for free
## AI Exposure
Tenable AI Exposure Request a demo
## OT/IoT Exposure
Tenable OT Security Request a demo
## Identity Exposure
Tenable Identity Exposure Request a demo
## Business needs
Active Directory
AI Security Posture Management (AI-SPM)
AWS security
Azure security
Cloud Security Posture Man
2020-08-29
Published
2021-11-03
Added to CISA KEV
Exploited in the wild