Cisco IOS, IOS XE and IOS XR Software TWAMP Denial of Service Vulnerability

published 2025-05-07 18 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-13922

cvss: 8.6; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 46%
public exploits: 0; none known

A vulnerability in the Two-Way Active Measurement Protocol (TWAMP) server feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the affected device to reload, resulting in a denial of service (DoS) condition. For Cisco IOS XR Software, this vulnerability could cause the ipsla_ippm_server process to reload unexpectedly if debugs are enabled.

This vulnerability is due to out-of-bounds array access when processing specially crafted TWAMP control packets. An attacker could exploit this vulnerability by sending crafted TWAMP control packets to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Note: For Cisco IOS XR Software, only the ipsla_ippm_server process reloads unexpectedly and only when debugs are enabled. The vulnerability details for Cisco IOS XR Software are as follows:    Security Impact Rating (SIR): Low    CVSS Base Score: 3.7    CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L

CISA SSVC

Exploitation: none
Automatable: yes
Technical impact: total
Assessed: 18 mo ago (2025-05-07)

Exploit prediction

0.55% chance of exploitation in the next 30 days, higher than 46% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	8.6	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Affected products

Cisco Cisco IOS XR Software

Classification

Weakness

CWE-20 Improper Input Validation

Technology feeds

Cisco IOS rss critical rss

References

sec.cloudapps.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-twamp-kV4FHugn
vendor-advisory

Sources

CVE List CVE-2025-20154
NVD CVE-2025-20154

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Summary