Asterisk PBX up to 13.23.0/14.7.7/15.6.0 HTTP Request resource management

CVSS Meta Temp Score
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CTI Interest Score
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A vulnerability, which was classified as problematic, has been found in Asterisk PBX up to 13.23.0/14.7.7/15.6.0 (Communications System). Affected by this issue is an unknown code of the file The manipulation as part of a HTTP Request leads to a resource management vulnerability. Using CWE to declare the problem leads to CWE-399. Impacted is availability. CVE summarizes:

There is a stack consumption vulnerability in the module of Asterisk through 13.23.0, 14.7.x through 14.7.7, and 15.x through 15.6.0 and Certified Asterisk through 13.21-cert2. It allows an attacker to crash Asterisk via a specially crafted HTTP request to upgrade the connection to a websocket.

The bug was discovered 09/20/2018. The weakness was released 09/24/2018 by Sean as confirmed mailinglist post (Bugtraq). The advisory is shared for download at This vulnerability is handled as CVE-2018-17281 since 09/20/2018. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are known technical details, but no exploit is available.

The vulnerability was handled as a non-public zero-day exploit for at least 1 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 117651 (FreeBSD : asterisk -- Remote crash vulnerability in HTTP websocket upgrade (77f67b46-bd75-11e8-81b6-001999f8d30b)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family FreeBSD Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 176509 (Debian Security Update for asterisk (DSA 4320-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published even before and not after the disclosure of the vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (117651). Entry connected to this vulnerability is available at 119382.






CPE 2.3info

CPE 2.2info


VulDB CVSS-B Score: 🔍
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VulDB Meta Base Score: 6.4
VulDB Meta Temp Score: 6.3

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
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NVD Base Score: 7.5
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Class: Resource management
CWE: CWE-399 / CWE-404
ATT&CK: Unknown

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

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EPSS Percentile: 🔍

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Current Price Estimation: 🔍


Nessus ID: 117651
Nessus Name: FreeBSD : asterisk -- Remote crash vulnerability in HTTP websocket upgrade (77f67b46-bd75-11e8-81b6-001999f8d30b)
Nessus File: 🔍
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Threat Intelligenceinfo

Interest: 🔍
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Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍


09/20/2018 🔍
09/20/2018 +0 days 🔍
09/20/2018 +0 days 🔍
09/21/2018 +1 days 🔍
09/24/2018 +2 days 🔍
09/24/2018 +0 days 🔍
09/24/2018 +0 days 🔍
09/25/2018 +1 days 🔍
05/17/2023 +1695 days 🔍


Advisory: 149453
Researcher: Sean
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-17281 (🔍)

SecurityTracker: 1041694
SecurityFocus: 105389 - Multiple Asterisk Products CVE-2018-17281 Remote Stack Overflow Vulnerability

See also: 🔍


Created: 09/25/2018 12:42 PM
Updated: 05/17/2023 07:03 PM
Changes: 09/25/2018 12:42 PM (76), 03/27/2020 07:48 AM (6), 05/17/2023 06:56 PM (5), 05/17/2023 07:03 PM (1)
Complete: 🔍


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