CVE-2018-15490

02.01.2019, 18:29

An issue was discovered in ExpressVPN on Windows. The Xvpnd.exe process (which runs as a service with SYSTEM privileges) listens on TCP port 2015, which is used as an RPC interface for communication with the client side of the ExpressVPN application. A JSON-RPC protocol over HTTP is used for communication. The JSON-RPC XVPN.GetPreference and XVPN.SetPreference methods are vulnerable to path traversal, and allow reading and writing files on the file system on behalf of the service.

Path Traversal

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
NIST	NIST	7.1 HIGH	LOCAL	LOW	LOW	CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
mitre	CNA	---				---
CVE	ADP	---				---

Base Score

CVSS 3.x

EPSS Score

Percentile: 26%

Vendor	Product	Version
expressvpn	expressvpn	-

𝑥

= Vulnerable software versions

Common Weakness Enumeration

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the software does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

References

https://medium.com/%40Wflki/https-medium-com-wflki-cve-2018-15490-expressvpn-local-privilege-escalation-d22c86fecc47