#VU105692 Improper access control in Cisco Systems, Inc products - CVE-2025-20144

Vulnerability identifier: #VU105692

Vulnerability risk: Medium

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2025-20144

CWE-ID: CWE-284

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Cisco IOS XR
Operating systems & Components / Operating system
IOS XR White box
Operating systems & Components / Operating system package or component
NCS540
Hardware solutions / Firmware
NCS560
Hardware solutions / Firmware
NCS5500
Hardware solutions / Firmware
NCS 5700 Series Routers
Hardware solutions / Routers & switches, VoIP, GSM, etc

Vendor: Cisco Systems, Inc

Description

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

The vulnerability exists due to incorrect handling of packets when a specific configuration of the hybrid access control list (ACL) exists. A remote attacker can bypass a configured ACL on the target device.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Cisco IOS XR: 7.10 - 7.11.1

IOS XR White box: All versions

NCS540: All versions

NCS560: All versions

NCS5500: All versions

NCS 5700 Series Routers: All versions

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External links
https://blog.apnic.net/2024/09/02/crafting-endless-as-paths-in-bgp/
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ncs-hybridacl-crMZFfKQ

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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.