Vulnerability identifier: #VU80767

Vulnerability risk: High

CVSSv3.1: 5.1 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2023-20191

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XR
Operating systems & Components / Operating system
NCS 5700 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
Cisco Network Convergence System 540 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc
NCS5500
Hardware solutions / Firmware
NCS560
Hardware solutions / Firmware
IOS XR White box
Operating systems & Components / Operating system package or component

Vendor: Cisco Systems, Inc

Description

The vulnerability allows a remote attacker to gain unauthorized access to otherwise restricted functionality.

The vulnerability exists due to incomplete support in the access control list (ACL) processing on MPLS interfaces in the ingress direction. A remote attacker can bypass an ACL on the affected device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 6.4.0 - 7.10

NCS 5700 Series Routers: All versions

NCS5500: All versions

NCS560: All versions

Cisco Network Convergence System 540 Series Routers: All versions

IOS XR White box: All versions

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External links
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-dnx-acl-PyzDkeYF

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.