Asterisk 13.x < 13.23.1 / 14.x < 14.7.8 / 15.x < 15.6.1 / 13.21 < 13.21-cert3 HTTP Websocket Stack Overflow (AST-2018-009)

medium Nessus Plugin ID 117808

Language:

New! Vulnerability Priority Rating (VPR)

Tenable calculates a dynamic VPR for every vulnerability. VPR combines vulnerability information with threat intelligence and machine learning algorithms to predict which vulnerabilities are most likely to be exploited in attacks. Read more about what VPR is and how it is different from CVSS.

VPR Score: 3.6

Synopsis

A telephony application running on the remote host is affected by a remote denial of service vulnerability.

Description

According to its SIP banner, the version of Asterisk running on the remote host is 13.x prior to 13.23.1, 14.x prior to 14.7.8, 15.x prior to 15.6.1, or 13.21 prior to 13.21-cert3. It is therefore, affected by an error related to the res_http_websocket.so module that allows a stack overflow error as described in AST-2018-009. This error can allow denial of service attacks.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Solution

Upgrade to Asterisk version 13.23.1 / 14.7.8 / 15.6.1 / 13.21-cert3 or later.

Alternatively, do not load the res_http_websocket.so module, thus disabling HTTP websocket access.

See Also

http://downloads.asterisk.org/pub/security/AST-2018-009.html

https://issues.asterisk.org/jira/browse/ASTERISK-28013

Plugin Details

Severity: Medium

ID: 117808

File Name: asterisk_ast_2018_009.nasl

Version: 1.4

Type: remote

Family: Misc.

Published: 9/27/2018

Updated: 11/1/2019

Dependencies: asterisk_detection.nasl

Configuration: Enable paranoid mode

Risk Information

Risk Factor: Medium

VPR Score: 3.6

CVSS Score Source: CVE-2018-17281

CVSS v2.0

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

Temporal Vector: CVSS2#E:U/RL:OF/RC:C

CVSS v3.0

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:2.3:a:digium:asterisk:*:*:*:*:*:*:*:*

Required KB Items: Settings/ParanoidReport, asterisk/sip_detected

Exploit Ease: No known exploits are available

Patch Publication Date: 9/20/2018

Vulnerability Publication Date: 9/20/2018

Reference Information

CVE: CVE-2018-17281