SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2018-0369

A vulnerability in the reassembly logic for fragmented IPv4 packets of Cisco StarOS running on virtual platforms could allow an unauthenticated, remote attacker to trigger a reload of the npusim process, resulting in a denial of service (DoS) condition.

HIGH 8.6EPSS 2.27%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (2.27%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

A vulnerability in the reassembly logic for fragmented IPv4 packets of Cisco StarOS running on virtual platforms could allow an unauthenticated, remote attacker to trigger a reload of the npusim process, resulting in a denial of service (DoS) condition. There are four instances of the npusim process running per Service Function (SF) instance, each handling a subset of all traffic flowing across the device. It is possible to trigger a reload of all four instances of the npusim process around the same time. The vulnerability is due to improper handling of fragmented IPv4 packets containing options. An attacker could exploit this vulnerability by sending a malicious IPv4 packet across an affected device. An exploit could allow the attacker to trigger a restart of the npusim process, which will result in all traffic queued toward this instance of the npusim process to be dropped while the process is restarting. The npusim process typically restarts within less than a second. This vulnerability affects: Cisco Virtualized Packet Core-Single Instance (VPC-SI), Cisco Virtualized Packet Core-Distributed Instance (VPC-DI), Cisco Ultra Packet Core (UPC). Cisco Bug IDs: CSCvh29613.

CVSS 3.0
8.6 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS
2.27% probability · 83th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-20
Affected
cisco/staros
Source
psirt@cisco.com
EPSS trend
0%3%5%27 October 2026: 2.27%27 October 202627 October 2026

EPSS 2.3% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.