CVE-2019-18790 Information

Description

An issue was discovered in channels/chan_sip.c in Sangoma Asterisk 13.x 16.x and 17.x and Certified Asterisk 13.21 because of an incomplete fix for CVE-2019-18351. 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.

CVSS Vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Reference

http://downloads.asterisk.org/pub/security/AST-2019-006.html https://lists.debian.org/debian-lts-announce/2019/11/msg00038.html https://www.asterisk.org/downloads/security-advisories

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

LOW

Availability Impact

LOW

Base Score

NONE

Base Severity

6.5