CVE-2019-1686

Cisco ASR 9000 Series Aggregation Services Routers ACL Bypass Vulnerability

Severity Score

8.6

*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

*Multiple Sources

Exploited in Wild

*KEV

Decision

Attend

*SSVC

Descriptions

A vulnerability in the TCP flags inspection feature for access control lists (ACLs) on Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, remote attacker to bypass protection offered by a configured ACL on an affected device. The vulnerability is due to incorrect processing of the ACL applied to an interface of an affected device when Cisco Express Forwarding load balancing using the 3-tuple hash algorithm is enabled. An attacker could exploit this vulnerability by sending traffic through an affected device that should otherwise be denied by the configured ACL. An exploit could allow the attacker to bypass protection offered by a configured ACL on the affected device. There are workarounds that address this vulnerability. Affected Cisco IOS XR versions are: Cisco IOS XR Software Release 5.1.1 and later till first fixed. First Fixed Releases: 6.5.2 and later, 6.6.1 and later.

Una vulnerabilidad en el indicador función de inspección de marcas TCP para listas de control de acceso (ACL) en ASR 9000 Series Aggregation Services de Cisco versión ASR 9000 Series podría permitir que un atacante remoto no identificado omita la protección ofrecida por una ACL configurada en un dispositivo afectado. La vulnerabilidad se debe a un procesamiento incorrecto de la ACL aplicada a una interfaz de un dispositivo afectado cuando se habilita el equilibrio de carga de Cisco Express Forwarding utilizando el algoritmo de hash de 3 tuplas. Un atacante podría aprovechar esta vulnerabilidad enviando tráfico por medio de un dispositivo afectado que, de lo contrario, debería ser rechazado por la ACL configurada. Una operación podría permitir al atacante omitir la protección ofrecida por una ACL configurada en el dispositivo afectado. Hay soluciones que abordan esta vulnerabilidad. Las versiones afectadas de Cisco IOS XR son: Cisco IOS XR Software Release versión 5.1.1 y posteriores hasta su primera reparación. Primeros lanzamientos fijos: versión 6.5.2 y posteriores, versión 6.6.1 y posteriores.

*Credits: N/A

CVSS Scores

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

High

Availability

None

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Changed

Confidentiality

None

Integrity

Low

Availability

None

Attack Vector

Network

Attack Complexity

Low

Authentication

None

Confidentiality

None

Integrity

Partial

Availability

None

* Common Vulnerability Scoring System

SSVC

Decision:Attend

Exploitation

None

Automatable

Yes

Tech. Impact

Partial

* Organization's Worst-case Scenario

Timeline

2018-12-06 CVE Reserved
2019-04-17 CVE Published
2024-09-07 EPSS Updated
2024-11-19 CVE Updated
---------- Exploited in Wild
---------- KEV Due Date
---------- First Exploit

CWE

CWE-284: Improper Access Control

CAPEC

References (2)

URL	Tag	Source
http://www.securityfocus.com/bid/108026	Third Party Advisory

URL	Date	SRC

URL	Date	SRC

URL	Date	SRC
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-iosxracl	2020-10-16

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"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9000v Search vendor "Cisco" for product "Asr 9000v"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9001 Search vendor "Cisco" for product "Asr 9001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9006 Search vendor "Cisco" for product "Asr 9006"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9010 Search vendor "Cisco" for product "Asr 9010"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9901 Search vendor "Cisco" for product "Asr 9901"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9904 Search vendor "Cisco" for product "Asr 9904"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9906 Search vendor "Cisco" for product "Asr 9906"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9910 Search vendor "Cisco" for product "Asr 9910"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9912 Search vendor "Cisco" for product "Asr 9912"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 5.1.1 < 6.5.2 Search vendor "Cisco" for product "Ios Xr" and version " >= 5.1.1 < 6.5.2"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9922 Search vendor "Cisco" for product "Asr 9922"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9000v Search vendor "Cisco" for product "Asr 9000v"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9001 Search vendor "Cisco" for product "Asr 9001"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9006 Search vendor "Cisco" for product "Asr 9006"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9010 Search vendor "Cisco" for product "Asr 9010"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9901 Search vendor "Cisco" for product "Asr 9901"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9904 Search vendor "Cisco" for product "Asr 9904"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9906 Search vendor "Cisco" for product "Asr 9906"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9910 Search vendor "Cisco" for product "Asr 9910"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9912 Search vendor "Cisco" for product "Asr 9912"	-	-	Safe
Cisco Search vendor "Cisco"	Ios Xr Search vendor "Cisco" for product "Ios Xr"	>= 6.5.3 < 6.6.1 Search vendor "Cisco" for product "Ios Xr" and version " >= 6.5.3 < 6.6.1"	-	Affected	in	Cisco Search vendor "Cisco"	Asr 9922 Search vendor "Cisco" for product "Asr 9922"	-	-	Safe