Vulnerability identifier: #VU10714

Vulnerability risk: Low

CVSSv3.1: 4.6 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2018-7287

CWE-ID: CWE-835

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Asterisk Open Source
Server applications / Conferencing, Collaboration and VoIP solutions

Vendor: Digium (Linux Support Services)

Description
The vulnerability allows a remote attacker to cause DoS condition on the target system.

The weakness exists in the res_http_websocket.c code due to insufficient length checks on WebSocket frames. A remote attacker can send send WebSocket frames with a zero-length payload, trigger a busy loop condition until the underlying socket on the system is closed and cause the service to crash.

Mitigation
Update to version 15.2.2.

Vulnerable software versions

Asterisk Open Source: 15.0.0 - 15.2.1

---

External links
http://downloads.asterisk.org/pub/security/AST-2018-006.html

---

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.