CVE-2021-1268

Cisco IOS XR Software IPv6 Flood Denial of Service Vulnerability

Severity Score

6.5

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Track

*SSVC

Descriptions

A vulnerability in the IPv6 protocol handling of the management interfaces of Cisco IOS XR Software could allow an unauthenticated, adjacent attacker to cause an IPv6 flood on the management interface network of an affected device. The vulnerability exists because the software incorrectly forwards IPv6 packets that have an IPv6 node-local multicast group address destination and are received on the management interfaces. An attacker could exploit this vulnerability by connecting to the same network as the management interfaces and injecting IPv6 packets that have an IPv6 node-local multicast group address destination. A successful exploit could allow the attacker to cause an IPv6 flood on the corresponding network. Depending on the number of Cisco IOS XR Software nodes on that network segment, exploitation could cause excessive network traffic, resulting in network degradation or a denial of service (DoS) condition.

Una vulnerabilidad en el manejo del protocolo IPv6 de las interfaces de administración del Software Cisco IOS XR, podría permitir a un atacante adyacente no autenticado causar una inundación de IPv6 en la red de la interfaz de administración de un dispositivo afectado. La vulnerabilidad se presenta porque el software reenvía incorrectamente paquetes IPv6 que contienen un destino de dirección de grupo de multidifusión local de nodo IPv6 y son recibidos en las interfaces de administración. Un atacante podría explotar esta vulnerabilidad al conectarse a la misma red que las interfaces de administración e inyectando paquetes IPv6 que contienen un destino de dirección de grupo de multidifusión local de nodo IPv6. Una explotación con éxito podría permitir al atacante causar una inundación de IPv6 en la red correspondiente. Dependiendo de la cantidad de nodos del Software Cisco IOS XR, en ese segmento de red, la explotación podría causar un tráfico de red excesivo, resultando en una degradación de la red o una condición de denegación de servicio (DoS)

*Credits: N/A

CVSS Scores

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Adjacent

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

None

Availability

High

Attack Vector

Adjacent

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

None

Availability

Partial

* Common Vulnerability Scoring System

SSVC

Decision:Track

Exploitation

None

Automatable

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2020-11-13 CVE Reserved
2021-02-04 CVE Published
2023-10-21 EPSS Updated
2024-11-08 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-1076: Insufficient Adherence to Expected Conventions

CAPEC

References (1)

URL	Tag	Source

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-xripv6-spJem78K	2023-11-07

Affected Vendors, Products, and Versions

Vendor		Product				Version		Other		Status
Vendor	Product	Version	Other	Status	<-- -->	Vendor	Product	Version	Other	Status
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	< 6.7.3 Search vendor "Cisco" for product "Ios Xr" and version " < 6.7.3"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1001 Search vendor "Cisco" for product "Ncs 1001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	< 6.7.3 Search vendor "Cisco" for product "Ios Xr" and version " < 6.7.3"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1002 Search vendor "Cisco" for product "Ncs 1002"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 7.1.0 < 7.1.3 Search vendor "Cisco" for product "Ios Xr" and version " >= 7.1.0 < 7.1.3"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1001 Search vendor "Cisco" for product "Ncs 1001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 7.1.0 < 7.1.3 Search vendor "Cisco" for product "Ios Xr" and version " >= 7.1.0 < 7.1.3"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1002 Search vendor "Cisco" for product "Ncs 1002"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 7.2.0 < 7.2.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 7.2.0 < 7.2.2"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1001 Search vendor "Cisco" for product "Ncs 1001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 7.2.0 < 7.2.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 7.2.0 < 7.2.2"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1002 Search vendor "Cisco" for product "Ncs 1002"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	7.3.0 Search vendor "Cisco" for product "Ios Xr" and version "7.3.0"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1001 Search vendor "Cisco" for product "Ncs 1001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	7.3.0 Search vendor "Cisco" for product "Ios Xr" and version "7.3.0"	-	Affected	in	Cisco Search vendor "Cisco"	Ncs 1002 Search vendor "Cisco" for product "Ncs 1002"	-	-	Safe