Apache CloudStack before 4.5.2 does not properly preserve VNC passwords when migrating KVM virtual machines, which allows remote attackers to gain access by connecting to the VNC server.

The VNC websocket frame decoder in QEMU allows remote attackers to cause a denial of service (memory and CPU consumption) via a large (1) websocket payload or (2) HTTP headers section.

Buffer overflow in the vnc_refresh_server_surface function in the VNC display driver in QEMU before 2.4.0.1 allows guest users to cause a denial of service (heap memory corruption and process crash) or possibly execute arbitrary code on the host via unspecified vectors, related to refreshing the server display surface.

Comodo GeekBuddy before 4.18.121 does not restrict access to the VNC server, which allows local users to gain privileges by connecting to the server.

Xen 4.5.x and earlier enables certain default backends when emulating a VGA device for an x86 HVM guest qemu even when the configuration disables them, which allows local guest users to obtain access to the VGA console by (1) setting the DISPLAY environment variable, when compiled with SDL support, or connecting to the VNC server on (2) ::1 or (3) 127.0.0.1, when not compiled with SDL support.

libvirt before 1.2.12 allow remote authenticated users to obtain the VNC password by using the VIR_DOMAIN_XML_SECURE flag with a crafted (1) snapshot to the virDomainSnapshotGetXMLDesc interface or (2) image to the virDomainSaveImageGetXMLDesc interface.

The HandleRFBServerMessage function in libvncclient/rfbproto.c in LibVNCServer 0.9.9 and earlier does not check certain malloc return values, which allows remote VNC servers to cause a denial of service (application crash) or possibly execute arbitrary code by specifying a large screen size in a (1) FramebufferUpdate, (2) ResizeFrameBuffer, or (3) PalmVNCReSizeFrameBuffer message.

The virDomainGetXMLDesc API in Libvirt before 1.2.11 allows remote read-only users to obtain the VNC password by using the VIR_DOMAIN_XML_MIGRATABLE flag, which triggers the use of the VIR_DOMAIN_XML_SECURE flag.

Integer overflow in TigerVNC allows remote VNC servers to cause a denial of service (crash) and possibly execute arbitrary code via vectors related to screen size handling, which triggers a heap-based buffer overflow, a similar issue to CVE-2014-6051.

Race condition in the VMware driver in OpenStack Compute (Nova) before 2014.1.4 and 2014.2 before 2014.2rc1 allows remote authenticated users to access unintended consoles by spawning an instance that triggers the same VNC port to be allocated to two different instances.

Integer overflow in the MallocFrameBuffer function in vncviewer.c in LibVNCServer 0.9.9 and earlier allows remote VNC servers to cause a denial of service (crash) and possibly execute arbitrary code via an advertisement for a large screen size, which triggers a heap-based buffer overflow.

Multiple cross-site scripting (XSS) vulnerabilities in vncal.js.php in the VN-Calendar plugin 1.0 and earlier for WordPress allow remote attackers to inject arbitrary web script or HTML via the (1) fs or (2) w parameter.

Citrix CloudPlatform (formerly Citrix CloudStack) 3.0.x before 3.0.6 Patch C does not properly restrict access to VNC ports on the management network, which allows remote attackers to have unspecified impact via unknown vectors.

virt-v2v before 0.8.4 does not preserve the VNC console password when converting a guest, which allows local users to bypass the intended VNC authentication by connecting without a password.

RealVNC VNC 5.0.6 on Mac OS X, Linux, and UNIX allows local users to gain privileges via a crafted argument to the (1) vncserver, (2) vncserver-x11, or (3) Xvnc helper.

Apple Remote Desktop before 3.7 does not properly use server authentication-type information during decisions about whether to present an unencrypted-connection warning message, which allows remote attackers to obtain sensitive information in opportunistic circumstances by sniffing the network during an unintended cleartext VNC session.

Format string vulnerability in Screen Sharing Server in Apple Mac OS X before 10.9 and Apple Remote Desktop before 3.5.4 allows remote attackers to execute arbitrary code via format string specifiers in a VNC username.

OpenStack Compute (Nova) Grizzly, Folsom (2012.2), and Essex (2012.1) allows remote authenticated users to gain access to a VM in opportunistic circumstances by using the VNC token for a deleted VM that was bound to the same VNC port.

Untrusted search path vulnerability in UltraVNC 1.0.8.2 allows local users to gain privileges via a Trojan horse vnclang.dll file in the current working directory, as demonstrated by a directory that contains a .vnc file. NOTE: some of these details are obtained from third party information.

Apple Remote Desktop before 3.6.1 does not recognize the "Encrypt all network data" setting during connections to third-party VNC servers, which allows remote attackers to obtain cleartext VNC session content by sniffing the network.