Vulnerability identifier: #VU24194

Vulnerability risk: Medium

CVSSv3.1: 6.7 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:P/RL:O/RC:C]

CVE-ID: CVE-2017-9447

CWE-ID: CWE-22

Exploitation vector: Network

Exploit availability: Yes

Vulnerable software:
Parallels Remote Application Server
Server applications / Application servers

Vendor: Parallels

Description

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error when processing directory traversal sequences (e.g. ".\\\") appended after the "RASHTML5Gateway" URL. A remote attacker can send a specially crafted HTTP request and read arbitrary files on the system.

PoC:

https://[host]/RASHTML5Gateway//..\\\..\\\..\\\..\\\..\\\windows\win.ini

Mitigation
Install update from vendor's website.

Vulnerable software versions

Parallels Remote Application Server: 15.5.15566 - 15.5.16140

---

External links
http://blog.runesec.com/2018/02/22/parallels-ras-path-traversal/

---

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. However, proof of concept for this vulnerability is available.