CVE-2019-12654: Cisco IOS and IOS XE Software Session Initiation Protocol Denial of Service Vulnerability

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-09-25 · updated 2026-06-17
Weakness: CWE-476

Description

A vulnerability in the common Session Initiation Protocol (SIP) library of Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected device, resulting in a denial of service (DoS) condition. The vulnerability is due to insufficient sanity checks on an internal data structure. An attacker could exploit this vulnerability by sending a sequence of malicious SIP messages to an affected device. An exploit could allow the attacker to cause a NULL pointer dereference, resulting in a crash of the iosd process. This triggers a reload of the device.

Affected products

Cisco IOS XE: 15.6(1)s4.2, 16.3.8, 16.9.1

References

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