RHSA-2015:2233 — Security Advisory

Updated tigervnc packages that fix two security issues, several bugs, and add various enhancements are now available for Red Hat Enterprise Linux 7.

Red Hat Product Security has rated this update as having Moderate security impact. Common Vulnerability Scoring System (CVSS) base scores, which give detailed severity ratings, are available for each vulnerability from the CVE links in the References section.

Virtual Network Computing (VNC) is a remote display system which allows users to view a computing desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients. The tigervnc packages contain a client which allows users to connect to other desktops running a VNC server.

An integer overflow flaw, leading to a heap-based buffer overflow, was found in the way TigerVNC handled screen sizes. A malicious VNC server could use this flaw to cause a client to crash or, potentially, execute arbitrary code on the client. (CVE-2014-8240)

A NULL pointer dereference flaw was found in TigerVNC's XRegion. A malicious VNC server could use this flaw to cause a client to crash. (CVE-2014-8241)

The tigervnc packages have been upgraded to upstream version 1.3.1, which provides a number of bug fixes and enhancements over the previous version. (BZ#1199453)

This update also fixes the following bug:

• The position of the mouse cursor in the VNC session was not correctly communicated to the VNC viewer, resulting in cursor misplacement. The method of displaying the remote cursor has been changed, and cursor movements on the VNC server are now accurately reflected on the VNC client. (BZ#1100661)

All tigervnc users are advised to upgrade to these updated packages, which correct these issues and add these enhancements.