Debian Security Advisory

DLA-2264-1 libvncserver -- LTS security update

Date Reported:
30 Jun 2020
Affected Packages:
Security database references:
In Mitre's CVE dictionary: CVE-2019-20839, CVE-2020-14397, CVE-2020-14399, CVE-2020-14400, CVE-2020-14401, CVE-2020-14402, CVE-2020-14403, CVE-2020-14404, CVE-2020-14405.
More information:

Several vulnerabilities have been discovered in libVNC (libvncserver Debian package), an implemenantation of the VNC server and client protocol.

  • CVE-2019-20839

    libvncclient/sockets.c in LibVNCServer had a buffer overflow via a long socket filename.

  • CVE-2020-14397

    libvncserver/rfbregion.c had a NULL pointer dereference.

  • CVE-2020-14399

    Byte-aligned data was accessed through uint32_t pointers in libvncclient/rfbproto.c.

  • CVE-2020-14400

    Byte-aligned data was accessed through uint16_t pointers in libvncserver/translate.c.

  • CVE-2020-14401

    libvncserver/scale.c had a pixel_value integer overflow.

  • CVE-2020-14402

    libvncserver/corre.c allowed out-of-bounds access via encodings.

  • CVE-2020-14403

    libvncserver/hextile.c allowed out-of-bounds access via encodings.

  • CVE-2020-14404

    libvncserver/rre.c allowed out-of-bounds access via encodings.

  • CVE-2020-14405

    libvncclient/rfbproto.c does not limit TextChat size.

For Debian 8 Jessie, these problems have been fixed in version 0.9.9+dfsg2-6.1+deb8u8.

We recommend that you upgrade your libvncserver packages.

Further information about Debian LTS security advisories, how to apply these updates to your system and frequently asked questions can be found at: