CVE-2025-20189 — HIGH (7.4)

Vulnerability Description

A vulnerability in the Cisco Express Forwarding functionality of Cisco IOS XE Software for Cisco ASR 903 Aggregation Services Routers with Route Switch Processor 3 (RSP3C) could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper memory management when Cisco IOS XE Software is processing Address Resolution Protocol (ARP) messages. An attacker could exploit this vulnerability by sending crafted ARP messages at a high rate over a period of time to an affected device. A successful exploit could allow the attacker to exhaust system resources, which eventually triggers a reload of the active route switch processor (RSP). If a redundant RSP is not present, the router reloads.

CVSS Score

7.4

HIGH

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Attack Vector

ADJACENT_NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

CHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Affected Products

Vendor	Product	Versions
Cisco	Ios Xe	3.16.0cs
Cisco	Asr 903	-

Related Weaknesses (CWE)

CWE-762

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/ciVendor Advisory

FAQ

What is CVE-2025-20189?

CVE-2025-20189 is a vulnerability with a CVSS score of 7.4 (HIGH). A vulnerability in the Cisco Express Forwarding functionality of Cisco IOS XE Software for Cisco ASR 903 Aggregation Services Routers with Route Switch Processor 3 (RSP3C) could allow an unauthenticat...

How severe is CVE-2025-20189?

CVE-2025-20189 has been rated HIGH with a CVSS base score of 7.4/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-20189?

Check the references section above for vendor advisories and patch information. Affected products include: Cisco Ios Xe, Cisco Asr 903.