CVE-2018-0369: A vulnerability in the reassembly logic for fragmented IPv4 packets of Cisco StarOS running on virtual platforms could allow an unauthenticated, remot...

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.

Metrics

EPSS Probability

2.30%

81.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Cisco	Staros	>= 21.3, < 21.3.15
Cisco	Staros	>= 21.4, < 21.5.7
Cisco	Staros	>= 21.6, < 21.6.4

References

http://www.securityfocus.com/bid/104723Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180711-staros-dosVendor Advisory
http://www.securityfocus.com/bid/104723Third Party Advisory, VDB Entry
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180711-staros-dosVendor Advisory

Timeline

Published: Jul 16, 2018
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is 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. 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.

How severe is CVE-2018-0369?

Severity scoring for CVE-2018-0369 is pending analysis. The EPSS model estimates a 2.30% probability of exploitation in the next 30 days.

How do I fix CVE-2018-0369?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.