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
Use CWE-20, Cisco vendor hub and Ios product page to widen CVE-2025-20154 into its surrounding weakness, vendor, and product context.
Compare it with CVE-2025-20352, CVE-2025-20363 and CVE-2025-20176 for nearby disclosures in the same product family. Additional editorial context is available in The Weekly Cybersecurity Brief: January 30th, 2026.