CVE-2019-18790

Severity: medium (CVSS 6.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-11-22 · updated 2026-06-17
Weakness: CWE-862

Description

An issue was discovered in channels/chan_sip.c in Sangoma Asterisk 13.x before 13.29.2, 16.x before 16.6.2, and 17.x before 17.0.1, and Certified Asterisk 13.21 before cert5. A SIP request can be sent to Asterisk that can change a SIP peer's IP address. A REGISTER does not need to occur, and calls can be hijacked as a result. The only thing that needs to be known is the peer's name; authentication details such as passwords do not need to be known. This vulnerability is only exploitable when the nat option is set to the default, or auto_force_rport.

Affected products

Debian Linux: 8.0, 9.0
Digium Asterisk: from 13.0.0 before 13.29.2; from 16.0.0 before 16.6.2; from 17.0.0 before 17.0.1 — fixed in 13.29.2, 16.6.2, 17.0.1
Digium Certified Asterisk: 13.21.0, 13.21.0-cert1, 13.21.0-cert2, 13.21.0-cert3, 13.21.0-cert4, 13.21.0-rc1

How to fix

Upgrade to a fixed version: Digium Asterisk 13.29.2, 16.6.2, 17.0.1. Check the vendor advisory for mitigations.

References

Get alerted when CVE-2019-18790 or the next vulnerability affects your stack