Signature Detail

HTTP: Digium Asterisk res_http_websocket HTTP Upgrade Request Denial of Service

A denial-of-service vulnerability has been reported in Digium Asterisk. The vulnerability is due to improper handling of HTTP Upgrade requests during initial WebSocket connection establishment within the res_http_websocket module of Asterisk. A remote attacker could exploit this vulnerability by sending crafted HTTP requests to the target server. Successful exploitation could result in a denial-of-service condition.

Extended Description

There is a stack consumption vulnerability in the res_http_websocket.so 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.

Affected Products

• Debian debian_linux 8.0
• Debian debian_linux 9.0
• Digium asterisk 13.0.0
• Digium asterisk 13.1.0
• Digium asterisk 13.10.0
• Digium asterisk 13.11.0
• Digium asterisk 13.12.0
• Digium asterisk 13.12.1
• Digium asterisk 13.12.2
• Digium asterisk 13.13.0
• Digium asterisk 13.14.0
• Digium asterisk 13.15.0
• Digium asterisk 13.16.0
• Digium asterisk 13.17.0
• Digium asterisk 13.18.0
• Digium asterisk 13.19.0
• Digium asterisk 13.2.0
• Digium asterisk 13.20.0
• Digium asterisk 13.21.0
• Digium asterisk 13.22.0
• Digium asterisk 13.23.0
• Digium asterisk 13.3.0
• Digium asterisk 13.4.0
• Digium asterisk 13.5.0
• Digium asterisk 13.6.0
• Digium asterisk 13.7.0
• Digium asterisk 13.8.0
• Digium asterisk 13.8.1
• Digium asterisk 13.8.2
• Digium asterisk 13.9.0
• Digium asterisk 14.0.0
• Digium asterisk 14.01
• Digium asterisk 14.0.1
• Digium asterisk 14.02
• Digium asterisk 14.0.2
• Digium asterisk 14.1
• Digium asterisk 14.1.0
• Digium asterisk 14.1.1
• Digium asterisk 14.1.2
• Digium asterisk 14.2
• Digium asterisk 14.2.0
• Digium asterisk 14.2.1
• Digium asterisk 14.3.0
• Digium asterisk 14.3.1
• Digium asterisk 14.4.0
• Digium asterisk 14.4.1
• Digium asterisk 14.5.0
• Digium asterisk 14.6.0
• Digium asterisk 14.6.1
• Digium asterisk 14.6.2
• Digium asterisk 14.7.0
• Digium asterisk 14.7.1
• Digium asterisk 14.7.2
• Digium asterisk 14.7.3
• Digium asterisk 14.7.4
• Digium asterisk 14.7.5
• Digium asterisk 14.7.6
• Digium asterisk 14.7.7
• Digium asterisk 15.0.0
• Digium asterisk 15.1.0
• Digium asterisk 15.2.0
• Digium asterisk 15.3.0
• Digium asterisk 15.4.0
• Digium asterisk 15.5.0
• Digium asterisk 15.6.0
• Digium certified_asterisk 11.6
• Digium certified_asterisk 13.1
• Digium certified_asterisk 13.13
• Digium certified_asterisk 13.21
• Digium certified_asterisk 13.8

References

• CVE: CVE-2018-17281
• URL: http://downloads.asterisk.org/pub/security/ast-2018-009.html