CVE-2019-1752: Cisco IOS

High severity, CVSS 7.5. EPSS: 2.5% chance of exploitation in the next 30 days.

A vulnerability in the ISDN functions of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause the device to reload. The vulnerability is due to incorrect processing of specific values in the Q.931 information elements. An attacker could exploit this vulnerability by calling the affected device with specific Q.931 information elements being present. An exploit could allow the attacker to cause the device to reload, resulting in a denial of service (DoS) condition on an affected device.

Affected products

• Cisco IOS: version 15.0(1)m only; version 15.0(1)m1 only; version 15.0(1)m2 only; version 15.0(1)m3 only; version 15.0(1)m4 only; version 15.0(1)m5 only; …
• Cisco IOS XE: version 3.8.0s only; version 3.8.1s only; version 3.8.2s only; version 3.9.0as only; version 3.9.0s only; version 3.9.1as only; …

Published 2019-03-28. Last modified 2026-06-17.