CVE-2019-16026: Cisco Mobility Management Entity Denial of Service Vulnerability

Severity: medium (CVSS 5.9 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2020-01-26 · updated 2026-06-17
Weakness: CWE-20

Description

A vulnerability in the implementation of the Stream Control Transmission Protocol (SCTP) on Cisco Mobility Management Entity (MME) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an eNodeB that is connected to an affected device. The vulnerability is due to insufficient input validation of SCTP traffic. An attacker could exploit this vulnerability by leveraging a man-in-the-middle position between the eNodeB and the MME and then sending a crafted SCTP message to the MME. A successful exploit would cause the MME to stop sending SCTP messages to the eNodeB, triggering a DoS condition.

Affected products

Cisco StarOS: before 21.16.1 — fixed in 21.16.1

How to fix

Upgrade to a fixed version: Cisco StarOS 21.16.1. Check the vendor advisory for mitigations.

References

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